Knowledge of the anatomical organization of the hamstring muscles is necessary to understand their functions, and to assist in the development of accurate clinical and biomechanical models. The hamstring muscles were examined by dissection in six embalmed human lower limbs with the purpose of clarifying their gross morphology. In addition to obtaining evidence for or against anatomical partitioning (as based on muscle architecture and pattern of innervation), data pertaining to architectural parameters such as fascicular length, volume, physiological cross-sectional area, and tendon length were collected. For each muscle, relatively consistent patterns of innervation were identified between specimens, and each was unique with respect to anatomical organization. On the basis of muscle architecture, three regions were identified within semimembranosus. However, this was not completely congruent with the pattern of innervation, as a primary nerve branch supplied only two regions, with the third region receiving a secondary branch. Semitendinosus comprised two distinct partitions arranged in series that were divided by a tendinous inscription. A singular muscle nerve or a primary nerve branch innervated each partition. In the biceps femoris long head the two regions were supplied via a primary nerve branch which divided into two primary branches or split into a series of branches. Being the only muscle to cross a single joint, biceps femoris short head consisted of two distinct regions demarcated by fiber direction, with each innervated by a separate muscle nerve. Architecturally, each muscle differed with respect to parameters such as physiological cross-sectional area, fascicular length and volume, but generally all partitions within an individual muscle were similar in fascicular length. The long proximal and distal tendons of these muscles extended into the muscle bellies thereby forming elongated musculotendinous junctions.

Prospective cross-sectional study. To examine the radiological and physical therapy diagnoses of lateral hip pain (LHP), and determine the validity of selected clinical variables for predicting gluteal tendon pathology. LHP is frequently encountered by clinicians. Further investigation is required to establish the specific pathologies implicated in the cause of LHP, and which clinical tests are useful in the assessment of this problem. Forty patients with unilateral LHP underwent a physical therapy examination followed by magnetic resonance imaging (MRI) studies. Three radiologists analyzed the images of both hips for signs of pathology. Interobserver reliability of the image analyses, the agreement between the physical therapy and radiological diagnoses, and the validity of the clinical tests were examined. Gluteus medius tendon pathology, bursitis, osteoarthritis and gluteal muscle atrophy (predominantly affecting gluteus minimus) were all implicated in the imaging report of LHP. While prevalent in symptomatic hips, abnormalities were also identified in asymptomatic hips, particularly relating to the diagnosis of bursitis. The strength of agreement between radiologists was variable and little agreement existed between the physical therapy and radiological diagnoses of pathology. Nine of the 26 clinical variables examined in relation to gluteal tendon pathology had likelihood ratios above 2.0 or below 0.5, but the associated 95% confidence intervals were large. The diagnosis of LHP is challenging and our results highlight some problems associated with the use of MRI as a diagnostic reference standard. This factor, together with the imprecise point estimates of the likelihood ratios, means that no firm conclusions can be made regarding the diagnostic utility of the clinical tests used in the assessment of gluteal tendon pathology.

Background: Abnormalities of the bursae in the vicinity of the greater trochanter have been implicated in the pathogenesis of lateral hip pain. The purpose of the present study was to investigate the detailed morphology of the bursae associated with the greater trochanter of the femur. Methods: The bursae deep to the tendons of each of the gluteal muscles were examined in eighteen embalmed human hips with use of macrodissection and histological techniques. The specimens were obtained from eight female and seven male donors who had had a mean age of seventy-eight years at the time of death. Results: A total of 106 bursae were identified in ten different locations, with an average of six bursae per hip. As many as four bursae were present beneath the gluteus maximus muscle and the fascia lata, including those normally thought of as the “trochanteric” bursae and the gluteofemoral bursa. Two bursae typically were found beneath the tendon of the gluteus medius muscle: the anterior subgluteus medius bursa and the piriformis (posterior subgluteus medius) bursa. In the majority of cases, a single bursa was located deep to the gluteus minimus tendon, although two different bursae were identified: the subgluteus minimus bursa and the secondary subgluteus minimus bursa. All of these bursae demonstrated a synovial lining, which was predominantly areolar in type. Conclusions: The present study revealed that numerous bursae are intimately associated with the greater trochanter and that at least two bursae are associated with each of the gluteal tendons. Clinical Relevance: The findings of the present study contrast with traditional anatomical descriptions and clinical teaching regarding the existence of a single “trochanteric” bursa. New information is also provided regarding the bursae located beneath the tendons of the gluteus medius and gluteus minimus. Improved knowledge of bursal anatomy will assist clinicians in accurately locating these structures.