Xinning Li
Boston University, Orthopaedic Surgery, Faculty Member
Background: Anterior cruciate ligament (ACL) tears are debilitating injuries frequently suffered by athletes. ACL reconstruction is indicated to restore knee stability and allow patients to return to prior levels of athletic performance.... more
Background: Anterior cruciate ligament (ACL) tears are debilitating injuries frequently suffered by athletes. ACL reconstruction is indicated to restore knee stability and allow patients to return to prior levels of athletic performance. While existing literature suggests that patient-reported outcomes are similar between bone–patellar tendon–bone (BTB) and hamstring tendon (HT) autografts, there is less information comparing return-to-sport (RTS) rates between the 2 graft types. Purpose: To compare RTS rates among athletes undergoing primary ACL reconstruction using a BTB versus HT autograft. Study Design: Systematic review; Level of evidence, 4. Methods: The MEDLINE, Embase, and Cochrane Library databases were searched, and studies that reported on RTS after primary ACL reconstruction using a BTB or HT autograft were included. Studies that utilized ACL repair techniques, quadriceps tendon autografts, graft augmentation, double-bundle autografts, allografts, or revision ACL reconst...
Shoulder metallosis with giant cell tumor formation is rarely seen in shoulder surgery. With an increase in shoulder arthroplasty and complex revision shoulder surgeries, clinicians should have an index of suspicion for possible... more
Shoulder metallosis with giant cell tumor formation is rarely seen in shoulder surgery. With an increase in shoulder arthroplasty and complex revision shoulder surgeries, clinicians should have an index of suspicion for possible metallosis in patients that presents with unexplained persistent pain with metal components on both the glenoid and humeral side. This case describes a 43-yearold female with a history of six prior shoulder surgeries who presented with shoulder metallosis and giant cell tumor formation after a screw from her open Latarjet procedure began rubbing against her Hemicap implant. She successfully underwent a revision total shoulder arthroplasty for post traumatic arthritis with pectoralis major transfer for her chronic subscapularis rupture and had complete symptom resolution.
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Purpose The purpose of this paper is to design a contract to coordinate the biomass molding fuel supply chain consisting of a supplier with uncertain supply and a producer with cyclical demand as well as improve the profit of this supply... more
Purpose The purpose of this paper is to design a contract to coordinate the biomass molding fuel supply chain consisting of a supplier with uncertain supply and a producer with cyclical demand as well as improve the profit of this supply chain. Design/methodology/approach In this paper, the supply chain model was build and all the variables and assumptions are set. Stackelberg game model was used to analyze and solve the problem. Furthermore, the authors give numerical examples and result analysis on the basis of data coming from field study and online information about a real biomass fuel supply chain. Findings The wholesale price with shortage penalty contract the authors proposed can coordinate the supply chain. And as the dominator of the supply chain, the producer can realize the redistribution of profits within the supply chain by determine the contract parameters. Research limitations/implications This one-to-one supply chain is a basic of complex supply chain system. Multi-t...
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Rotator cuff repair (RCR) is an effective procedure to relieve shoulder pain and dysfunction. Postoperative physical therapy (PT) plays an integral role in the overall success of RCR. Insurance status has been shown to be an important... more
Rotator cuff repair (RCR) is an effective procedure to relieve shoulder pain and dysfunction. Postoperative physical therapy (PT) plays an integral role in the overall success of RCR. Insurance status has been shown to be an important predictor of postoperative PT utilization. This study evaluated the effect of insurance status on access to PT services following RCR. One hundred thirty-eight PT clinics were contacted in the Greater Boston metropolitan area. Clinics were contacted on two separate occasions and presented with a fictitious acutely postoperative RCR patient in need of PT. Insurance status was reported as Medicaid or private insurance. Overall, 133 (96.4%) accepted private insurance, whereas only 71 (51.4%) accepted Medicaid (P=0.019). Medicaid patients were offered a first available appointment at a mean of 8.3 days (95% CI: 7.13-9.38, range: 0-31) versus a mean of 6.3 days (95% CI: 5.3-7.22, range: 0-19, P=0.001) for private patients. Clinic location was not associated...
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Background: For athletes, a return to preinjury activity levels with minimal time away is a metric indicative of successful recovery. The knowledge of this metric would be helpful for the sports medicine specialist to advise patients on... more
Background: For athletes, a return to preinjury activity levels with minimal time away is a metric indicative of successful recovery. The knowledge of this metric would be helpful for the sports medicine specialist to advise patients on appropriate expectations after surgery. Purpose: To evaluate the rate and amount of time needed for athletes to return to sport (RTS) after different surgical treatments for anterior shoulder instability. Study Design: Systematic review and meta-analysis. Methods: The MEDLINE, EMBASE, and Cochrane databases were searched for articles relevant to athletes’ RTS after surgical anterior shoulder stabilization with variants of the Latarjet and Bankart procedures. Article selection was based on relevant inclusion and exclusion criteria. After the articles were reviewed, the data pertinent to rates of and time to RTS were extracted, compiled, and analyzed. Results: Sixteen articles met the inclusion criteria. Based on these articles, the rate of RTS was 97....
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Previous studies have examined the relationship between total hip arthroplasty (THA) and insurance status in small cohorts. This study evaluates the effect of patient insurance status on complications after primary elective THA using the... more
Previous studies have examined the relationship between total hip arthroplasty (THA) and insurance status in small cohorts. This study evaluates the effect of patient insurance status on complications after primary elective THA using the Nationwide Inpatient Sample. All patients undergoing primary elective THA from 1998 to 2011 were included. Patient demographics, comorbidities, and complications were collected and compared based on insurance type. Multivariable logistic regression and a matched cohort analysis were performed. About 515,037 patients (53.7% Medicare, 40.1% private insurance, 3.9% Medicaid/uninsured, and 2.2% other) were included, who underwent elective THA. Privately insured patients had fewer medical complications (odds ratio, 0.80; P < 0.001), whereas patients with Medicaid or no insurance demonstrated no notable difference (odds ratio, 1.03; P = 0.367) compared with Medicare patients. Similar trends were found for both surgical complications and mortality, favoring lower complication rates for privately insured patients. Furthermore, patients with private insurance tend to go to higher volume hospitals for total hip replacement surgery compared to those with Medicare insurance. Patients with government-sponsored insurance (Medicare or Medicaid) or no insurance have higher risk of medical complications, surgical complications, and mortality after primary elective THA compared with privately insured patients. Insurance status should be considered an independent risk factor for stratifying patients before THA procedures.
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In the senior author's (X.L.) orthopaedic sports medicine clinic in the United States (US), patients appear to have difficulty finding physical therapy (PT) practices that accept Medicaid insurance for postoperative rehabilitation. To... more
In the senior author's (X.L.) orthopaedic sports medicine clinic in the United States (US), patients appear to have difficulty finding physical therapy (PT) practices that accept Medicaid insurance for postoperative rehabilitation. To determine access to PT services for privately insured patients versus those with Medicaid who underwent anterior cruciate ligament (ACL) reconstruction in the largest metropolitan area in the state of Massachusetts, which underwent Medicaid expansion as part of the Affordable Care Act. Cross-sectional study. Locations offering PT services were identified through Google, Yelp, and Yellow Pages internet searches. Each practice was contacted and queried about health insurance type accepted (Medicaid [public] vs Blue Cross Blue Shield [private]) for postoperative ACL reconstruction rehabilitation. Additional data collection points included time to first appointment, reason for not accepting insurance, and ability to refer to a location accepting insura...
Ultrasonography is an imaging modality that facilitates the diagnosis of pathology and injection therapy without exposing the patient to radiation. In addition, ultrasonography has become popular because of its portability, low cost, and... more
Ultrasonography is an imaging modality that facilitates the diagnosis of pathology and injection therapy without exposing the patient to radiation. In addition, ultrasonography has become popular because of its portability, low cost, and production of real-time tomographic images that provide a cross-sectional view of anatomic structures. Despite its benefits and widespread adoption in general medicine and other specialties, however, ultrasonography is not as well adapted as a diagnostic and research tool in orthopaedic surgery. An understanding of the basic principles of ultrasonography and the evidence supporting its use can aid the orthopaedic surgeon in applying this modality appropriately in clinical practice.
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Injuries to the labrum, joint capsule (in particular the inferior glenohumeral ligament), cartilage, and glenoid periosteum are associated with anterior shoulder instability. The goal of this review is to provide common radiographic... more
Injuries to the labrum, joint capsule (in particular the inferior glenohumeral ligament), cartilage, and glenoid periosteum are associated with anterior shoulder instability. The goal of this review is to provide common radiographic images and findings in patients with anterior shoulder instability. Furthermore, we will demonstrate the best methods for measuring anterior glenoid bone loss. Magnetic resonance (MR) imaging is highly relied upon for evaluating anterior shoulder instability and can diagnose soft tissue injuries with high sensitivity. While 3D computed tomography (CT) scan has been considered the optimal tool for evaluating osseous defects, certain MR imaging sequences have been shown to have similar diagnostic accuracy. Repair of Bankart lesions is critical to stabilizing the shoulder, and in the recent years, there has been an increasing focus on imaging to accurately characterize and measure glenoid bone loss to properly indicate patients for either arthroscopic repai...
The aims of this review article are (a) to describe the principles of morphologic and compositional magnetic resonance imaging (MRI) techniques relevant for the imaging of knee cartilage repair surgery and their application to... more
The aims of this review article are (a) to describe the principles of morphologic and compositional magnetic resonance imaging (MRI) techniques relevant for the imaging of knee cartilage repair surgery and their application to longitudinal studies and (b) to illustrate the clinical relevance of pre- and postsurgical MRI with correlation to intraoperative images. First, MRI sequences that can be applied for imaging of cartilage repair tissue in the knee are described, focusing on comparison of 2D and 3D fast spin echo and gradient recalled echo sequences. Imaging features of cartilage repair tissue are then discussed, including conventional (morphologic) MRI and compositional MRI techniques. More specifically, imaging techniques for specific cartilage repair surgery techniques as described above, as well as MRI-based semiquantitative scoring systems for the knee cartilage repair tissue-MR Observation of Cartilage Repair Tissue and Cartilage Repair OA Knee Score-are explained. Then, c...
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Recent evidence has demonstrated that A kinase interacting protein 1 (AKIP1), a molecular regulator of protein kinase A, was overexpressed in breast cancer. However, the prognostic and biological role of AKIP1 in breast cancer is still... more
Recent evidence has demonstrated that A kinase interacting protein 1 (AKIP1), a molecular regulator of protein kinase A, was overexpressed in breast cancer. However, the prognostic and biological role of AKIP1 in breast cancer is still elusive. The purpose of our study was to elucidate the role and molecular mechanism of AKIP1 in breast cancer development. The mRNA levels of AKIP1 in breast cancer and paired normal breast tissues were examined by quantitative real-time PCR. The relationship of AKIP1 expression with clinicopathological characteristics and clinical prognosis of breast cancer patients was investigated. In vitro migration and invasion assays were performed in MCF-7 and SK-BR-3 cells to determine its role in metastasis and the possible mechanism. The result showed that AKIP1 expression was up-regulated in breast cancer tissues compared with that in normal breast tissues. High expression of AKIP1 was associated significantly with advanced tumor stage (P<0.001), tumor s...
The North American Traveling Fellowship (NATF) is one of the flagship tours of the American Orthopaedic Association (AOA). NATF is geared toward advancing the careers of young orthopaedic surgeons through the promotion of clinical,... more
The North American Traveling Fellowship (NATF) is one of the flagship tours of the American Orthopaedic Association (AOA). NATF is geared toward advancing the careers of young orthopaedic surgeons through the promotion of clinical, scientific, and social exchange. The 2015 tour had a major emphasis on the development of leadership in the field of orthopaedics through close interactions and meetings with departmental chairs and administrators, as well as with hospital and medical school leaders. The 2015 NATF tour was in the Midwest corridor of Canada and the United States. The 5 fellows included specialists in spine, trauma, sports medicine, and shoulder and elbow surgery. Lifelong friendships and collaborations were formed during the tour. We visited 14 centers, and each site/host made great efforts to make us feel welcome and also organized excellent academic and social programs. By the conclusion of the tour, it was clear to all of us that this was a once in a lifetime experience...
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Computed tomography (CT) scan is the standard for the preoperative assessment of glenoid version and morphology before total shoulder arthroplasty. However, the capacity of magnetic resonance imaging (MRI) to visualize bone morphology has... more
Computed tomography (CT) scan is the standard for the preoperative assessment of glenoid version and morphology before total shoulder arthroplasty. However, the capacity of magnetic resonance imaging (MRI) to visualize bone morphology has improved with advancing technology. The purpose of this study was to compare the accuracy of MRI to CT for assessment of glenoid version and Walch classification. Three fellowship-trained shoulder surgeons assessed glenoid version and Walch classification of 30 patients with primary shoulder osteoarthritis who received both CT and MRI scans before total shoulder arthroplasty. Version measurements, Walch classification, and observer agreement were compared. Mean glenoid version was -15.5° and -18.6° by CT and MRI, respectively (P = .17). Interobserver reliability coefficients were good for both imaging modalities (CT, 0.73; MRI, 0.62). Intraobserver coefficients were good to excellent for CT (range, 0.76-0.87) and good for MRI (range, 0.75-0.79). For Walch classification, interobserver reliability for both modalities was merely fair, whereas intraobserver reliability was moderate to good. Although identification of type A1, A2, and B1 was nearly identical between CT and MRI, there was observer disagreement on type B2 (P = .001) and C glenoids (P = .03). Specifically, MRI underidentified type B2 and overidentified type C compared with CT. MRI is largely comparable to CT scan for evaluation of the glenoid, with similar measurements of version and identification of less extreme Walch glenoids. However, MRI is less accurate at distinguishing between type B2 and C glenoids.
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Posterior shoulder instability is less common and potentially more difficult to diagnose clinically and radiographically compared with anterior shoulder instability. Radiographic findings including posterior labral tears, increased... more
Posterior shoulder instability is less common and potentially more difficult to diagnose clinically and radiographically compared with anterior shoulder instability. Radiographic findings including posterior labral tears, increased retroversion, presence of glenoid dysplasia, and increased capsular area are associated with symptomatic recurrent posterior shoulder instability. This study aimed to determine the prevalence and severity of associated radiographic parameters found on magnetic resonance arthrograms (MRAs) in patients with arthroscopically confirmed isolated posterior labral tears and symptomatic recurrent posterior shoulder instability, compared with an age-matched cohort of patients without posterior instability or labral injury confirmed with shoulder arthroscopy. Cross-sectional study, Level of evidence, 3. Patients who received a preoperative standard shoulder MRA at an academic institution over a 5-year period and had symptomatic posterior instability and received a ...
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To evaluate whether anterior cruciate ligament (ACL) allograft irradiation is effective for sterility without compromising graft integrity and increasing failure rate. A literature search was conducted using PubMed, Cochrane, and Google.... more
To evaluate whether anterior cruciate ligament (ACL) allograft irradiation is effective for sterility without compromising graft integrity and increasing failure rate. A literature search was conducted using PubMed, Cochrane, and Google. The following search terms were used: &amp;amp;amp;amp;amp;amp;quot;Gamma irradiation AND anterior cruciate ligament AND allograft&amp;amp;amp;amp;amp;amp;quot; with a return of 30 items. Filters used included: English language, years 1990-2015. There were 6 hits that were not reviewed, as there were only abstracts available. Another 5 hits were discarded, as they did not pertain to the topic of interest. There were 9 more articles that were excluded: Three studies were performed on animals and 6 studies were meta-analyses. Therefore, a total of 10 articles were applicable to review. There is a delicate dosing crossover where gamma irradiation is both effective for sterility without catastrophically compromising the structural integrity of the graft. Of note, low dose irradiation is considered less than 2.0 Mrad, moderate dose is between 2.1-2.4 Mrad, and high dose is greater than or equal to 2.5 Mrad. Based upon the results of the literature search, the optimal threshold for sterilization was found to be sterilization at less than 2.2 Mrad of gamma irradiation with the important caveat of being performed at low temperatures. The graft selection process also must include thorough donor screening and testing as well as harvesting the tissue in a sterile fashion. Utilization of higher dose (≥ 2.5 Mrad) of irradiation causes greater allograft tissue laxity that results in greater graft failure rate clinically in patients after ACL reconstruction. Allograft ACL graft gamma irradiated with less than 2.2 Mrad appears to be a reasonable alternative to autograft for patients above 25 years of age.
This study compared the incidence and pattern of potential nerve injuries between reverse shoulder (RSA) and total shoulder arthroplasty (TSA) using intraoperative neuromonitoring. Our hypothesis was that RSA has a greater risk of nerve... more
This study compared the incidence and pattern of potential nerve injuries between reverse shoulder (RSA) and total shoulder arthroplasty (TSA) using intraoperative neuromonitoring. Our hypothesis was that RSA has a greater risk of nerve injury than TSA due to arm lengthening. We reviewed 36 consecutive patients who underwent RSA (n = 12) or TSA (n = 24) with intraoperative neuromonitoring. The number of nerve alerts was recorded for each stage of surgery. Neurologic function was assessed preoperatively and postoperatively at routine follow-up visits. Predictive factors for increased intraoperative nerve alerts and clinically detectable neurologic deficits were determined. There were nearly 5 times as many postreduction nerve alerts per patient in the RSA cohort compared with the TSA cohort (2.17 vs. 0.46). There were 17 unresolved nerve alerts postoperatively, with only 2 clinically detectable nerve injuries, which fully resolved by 6 months postoperatively. A preoperative decrease ...
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The treatments of avascular osteonecrosis (AVN) include both conservative and surgical methods which are dependent on the stage and progression of the disease. The vasoactive- prostaglandin-analogue iloprost (PGI2) has been utilized in... more
The treatments of avascular osteonecrosis (AVN) include both conservative and surgical methods which are dependent on the stage and progression of the disease. The vasoactive- prostaglandin-analogue iloprost (PGI2) has been utilized in several areas of medicine and recently has been used for the treatment of AVN. A total of 108 patients with 136 osteonecrosis of different joints, etiology and severity were treated with iloprost. The mean follow-up was 49.71 months: range 15-96 months, and outcome measurements recorded regarding subjective complaints, visual analog scale (pain), function and survival. The outcome scores used include the Harris Hip Score, Knee Society score, Foot and Ankle Survey, visual analogue scale (VAS) and a separate questionnaire. The location and etiology of AVN in our study demonstrated the typical pattern. All of the observed side effects of the therapy were minor and completely reversible. Most of patients (74.8%) showed a significant improvement of subject...
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Two elite female athletes presented with anterior knee pain with range of motion and reproducible tenderness to palpation. Diagnostic arthroscopy was performed in both cases resulting in excision of a nodular pigmented villonodular... more
Two elite female athletes presented with anterior knee pain with range of motion and reproducible tenderness to palpation. Diagnostic arthroscopy was performed in both cases resulting in excision of a nodular pigmented villonodular synovitis (PVNS) in the first patient and scar tissue in the second patient. Correct diagnosis of anterior knee pain in the elite female athlete can present a challenge to clinicians. Although patellofe-moral pain is the most common diagnosis, other uncommon causes include PVNS and residual scar formation in patients with a history of surgery or trauma. Magnetic resonance imaging (MRI) images are helpful in confirming the diagnosis, however, in a subset of patients, the physician must rely on clinical suspicion and physical exam to make the proper diagnosis. Given the possibility of a false negative MRI images, patients with persistent anterior knee pain with a history of knee surgeries and focal tenderness reproducible on physical exam may benefit from a...
Total elbow arthroplasty (TEA) is utilized in the treatment of rheumatoid and post-traumatic elbow arthritis. TEA is a relatively low volume surgery in comparison to other types of arthroplasty and therefore little is known about current... more
Total elbow arthroplasty (TEA) is utilized in the treatment of rheumatoid and post-traumatic elbow arthritis. TEA is a relatively low volume surgery in comparison to other types of arthroplasty and therefore little is known about current surgical utilization, patient demographics and complication rates in the United States. The purpose of our study is to evaluate the current practice trends and associated inpatient complications of TEA at academic centers in the United States. We queried the University Health Systems Consortium administrative database from 2007 to 2011 for patients who underwent an elective TEA. A descriptive analysis of demographics was performed which included patient age, sex, race, and insurance status. We also evaluated the following patient clinical benchmarks: hospital length of stay (LOS), hospital direct cost, inhospital mortality, complications, and 30-day readmission rates. Our cohort consisted of 3146 adult patients (36.5% male and 63.5% female) with an ...
Shoulder arthroplasty in individuals aged 50 years or younger reportedly leads to worse outcomes than in older patients. Current methods of determining survivorship may be inadequate and may not reflect actual patient definitions of... more
Shoulder arthroplasty in individuals aged 50 years or younger reportedly leads to worse outcomes than in older patients. Current methods of determining survivorship may be inadequate and may not reflect actual patient definitions of satisfaction. The purpose of this study is to evaluate and contrast the survival of patient satisfaction and implant survival in the youngest reported patients undergoing either a primary hemiarthroplasty (HA) or total shoulder arthroplasty (TSA) using a third-generation stemmed prosthesis. Outcomes in 71 patients aged 50 years or younger who were treated with primary HA or TSA were evaluated for patient satisfaction and implant survival rates. Patient satisfaction survival was based on yes or no answers to 2 binary questions regarding willingness to undergo surgery again and whether surgery improved the patient&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s shoulder. The Kaplan-Meier patient satisfaction survival rates at 5 years were 71.6% (95% confidence interval [CI], 46%-87%) for HAs and 95% (95% CI, 81%-99%) for TSAs. Multivariable regression analysis implicated postoperative pain as the primary causative factor for failure of patient satisfaction in all patients. In contrast, the implant survival rates at 5 years were 89% (95% CI, 69%-96%) for HAs and 95% (CI, 85%-100%) for TSAs. Patients aged 50 years or younger who undergo shoulder arthroplasty have declining rates of self-reported satisfaction despite high implant survival rates, and this finding highlights the discordance between patient satisfaction and implant survival. Primary TSA outperforms HA in both implant survival and patient satisfaction survival rates at short-term follow-up. Future studies and registries must incorporate measurements of patient satisfaction and not just revision rates to truly interpret outcomes.
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Normal hip range of motion (ROM) is essential in running and transfer of energy from lower to upper extremities during overhead throwing. Dysfunctional hip ROM may alter lower extremity kinematics and predispose athletes to hip and groin... more
Normal hip range of motion (ROM) is essential in running and transfer of energy from lower to upper extremities during overhead throwing. Dysfunctional hip ROM may alter lower extremity kinematics and predispose athletes to hip and groin injuries. The purpose of this study is characterize hip internal/external ROM (Arc) and its effect on the risk of hip, hamstring, and groin injuries in professional baseball players. Bilateral hip internal and external ROM was measured on all baseball players (N=201) in one professional organization (major and minor league) during spring training. Players were organized according to their respective positions. All injuries were documented prospectively for an entire MLB season (2010 to 2011). Data was analyzed according to position and injuries during the season. Total number of players (N=201) with an average age of 24±3.6 (range=17-37). Both pitchers (N=93) and catchers (N=22) had significantly decreased mean hip internal rotation and overall hip ...
To investigate the expression and role of PBRM1 in breast cancer, and to evaluate the clinical and prognostic significance of PBRM1 protein in patients with breast cancer. The expression of PBRM1 was examined in breast cancer tissue and... more
To investigate the expression and role of PBRM1 in breast cancer, and to evaluate the clinical and prognostic significance of PBRM1 protein in patients with breast cancer. The expression of PBRM1 was examined in breast cancer tissue and paired non-cancerous tissues by real-time PCR. Moreover, PBRM1 protein expression was evaluated by immunohistochemistry in 150 paraffin-embedded breast cancer specimens. The correlation between PBRM1 expression and clinicopathological features were statistically analyzed. The status of PBRM1 protein in breast cancer tissues is much lower than that in paracarcinoma tissues. Low PBRM1 expression was positively correlated with tumor stage (P =0.003) and lymph node metastasis (P =0.013). The overall (P =0.003) and recurrent-free survival (P =0.001) of the patients with high PBRM1 expression was significantly lower than the low PBRM1 expression group. Multivariate analysis showed that the expression of PBRM1 was an independent factor of overall survival f...
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ABSTRACT Microwave heating technology has been used in many fields as a means of selective, volumetric, and instantaneous heating. In the process, input electrical energy is first converted to microwave energy, which is then absorbed by a... more
ABSTRACT Microwave heating technology has been used in many fields as a means of selective, volumetric, and instantaneous heating. In the process, input electrical energy is first converted to microwave energy, which is then absorbed by a dielectric medium and changed into thermal energy (effective heat). The energy utilization efficiency of this process is of particular concern because it provides an important index of economic performance. A good understanding of these efficiencies via quantitative measurements is necessary to optimize the microwave heating process and to use it more effectively. The research reported here divided the microwave heating process into two stages, measured their energy utilization efficiencies in detail, and studied the effects of various factors. It was found that the heating body position in microwave cavity, the heating medium type, the microwave output power and the geometry parameters of heating medium like volume can all significantly influence the energy efficiencies. But even for the best optimized microwave heating process, the total energy efficiency can only amount to about 0.8. This work built up a general idea for understanding the issue of energy utilization efficiency in microwave heating processes through a quantitative method, and provided a feasible way to assess energy utilization characteristics of any microwave heating process or to test microwave absorption abilities of different media.