Conjoint Tendon Research Articles

Paper 87: What is the Stabilizing Mechanism of the Latarjet Procedure?

The Latarjet procedure is one of common ones for patients with anterior instability of the shoulder and its excellent clinical results have been reported. It has also been used as a bone-grafting procedure in patients with a large glenoid defect. “Sling effect of the subscapularis muscle” or “bone block effect of the coracoid process” has been believed as a main stabilizing mechanism of this procedure. However, the true mechanism is still unknown and there have been no biomechanical studies in the literature. The purpose of this study was to clarify the stabilizing mechanism of the Latarjet procedure for patients with anterior instability and ones with a large glenoid defect. Seven fresh-frozen cadaveric shoulders (mean age, 76 years) were investigated. The skin, subcutaneous tissue, and deltoid were removed preserving the rotator cuff muscles. Two arm positions (60° of abduction and maximum external rotation and neutral rotation) were chosen to simulate the terminal and mid-range conditions. With use of a custom multiaxis electromechanical testing machine with a six-degrees-of-freedom load-cell, the humeral head was translated 10 mm in the anterior direction. With a 50-N axial force constantly applied to the humerus in order to keep the humeral head centered in the glenoid fossa, the peak translational force was determined under eight sequential conditions: in the terminal range, 1) with the capsule intact, 2) after the creation of a simulated Bankart lesion, 3) after the Latarjet procedure, 4) after sectioning the conjoint tendon, 5) after sectioning the subscapularis tendon; in the mid-range, 6) after the creation of a large anterior glenoid defect (6mm width), 7) after the Latarjet procedure with and without applied load, 8) after Bankart repair. A 10-N and 2.5-N load was applied to the subscapularis and conjoint tendons, respectively. We followed G Walch's surgical technique. In the terminal range, the peak translational force with intact capsule was 157 ± 17, which significantly decreased down to 53 ± 26 after creating a Bankart lesion (p = 0.0004) and significantly increased to 131 ± 25 after the Latarjet procedure (p = 0.0010). After sectioning the conjoint and subscapularis tendons, the force was 112 ± 24, 107 ± 22 (19% decrease compared to that after the Latarjet procedure) (p < 0.0001), respectively. In the mid-range, the force with intact capsule was 67 ± 8, which significantly decreased to 17 ± 4 after creating a large glenoid defect (p < 0.0001) and did not return (33 ± 4) to the intact condition even after Bankart repair. However, it was significantly increased to 63 ± 6 (p < 0.0001) and 73 ± 4 (p < 0.0001), respectively, after the Latarjet procedure with and without load. Percentage contribution to the increase of the stability was 82% after the Latarjet procedure without load, 18% that with load, respectively. From our results, the stabilizing mechanism of the Latarjet procedure both in the terminal and mid-range motion was demonstrated. In the terminal range, 81% of the stability was contributed by the shortening of the anterior capsule including the anteroinferior glenohumeral ligament (re-tension effect), and the contribution of sling effect which many have believed was only 19%. On the other hand, in the mid-range, 82% of the stability was contributed by reconstruction of the glenoid concavity (glenoid plasty effect) and 18% by sling effect. Thus, it was demonstrated that the Latarjet procedure had a reasonable stabilizing mechanism as a re-stabilizing procedure for shoulders not only with anterior instability but also with a large glenoid defect.

OSTEOTOMIES OF THE CORACOID PROCESS: AN ANATOMICAL STUDY

Objective: Relate the main tendinous and ligamentous structures attached in the coracoid process, correlating it to several levels of osteotomy and describing the involved structures. Methods: Thirty shoulders were dissected. The coracoid process with mainly inserted anatomic structures was dissected, and five levels of osteotomy (1.0; 1.5; 2.0; 2.5; 3.0 cm) were made from the apex of the process and the mainly involved structures were recorded. Results: In osteotomies of 1.0 cm, in 100% of the cases only the conjoint tendon (CT). In osteotomies of 1.5 cm there were 63.33% of cases involved with the CT and the Pectoralis minor (PMi), in 20% of cases only the CT, and in 16.66% the CT, PMi, and the coracohumeral ligament (CUL). In osteotomies of 2.0 cm, in 80% of the shoulders, the osteotomies embraced the CT, PMi and the CUL, and in 20% only the CT and the PMi were involved. In the osteotomies of 2.5cm there was involvement of the CT, PMi and CUL in 100% of cases. In the osteotomies of 3.0cm, six cases (20%) have presented an injury on the trapezoid ligament, and in 100% of these osteotomies, the osteotomized distal fragment had embraced the CT, PMi, CUL. Conclusion: The knowledge of anatomic structures inserted and involved in the osteotomies cuts of the coracoid process is very importan to lead with osteotomies performed in the treatment techniques of the coracoid process. Osteotomies of 3.0 cm can injure the trapezoid ligament.

Mechanisms of proximal hamstring rupture in a non-athlete healthy middle-aged female

To present an explicatory pathophysiological model for the rare clinical case of a total proximal hamstring rupture for the first time in the literature. A non-athletic healthy female (49 years) experienced a complete rupture of the right conjoint tendon of the biceps femoris (long head) and semitendinosus muscle while slipping down a lawn-covered slope (eccentric hip flexion and knee extension during stance phase of gait after heel-strike). A hamstring rupture was diagnosed by clinical examination and confirmed by magnet resonance imaging (MRI). Surgical reattachment of the conjoint tendon to the ischial tuberosity was performed. One year after surgery, she experienced no pain or functional impairment. Histological analysis and immune-histochemical staining (vascular endothelial growth factor - receptor 2) of a biopsy taken intra-operatively revealed signs of fibroblast proliferation and vasculoneogenesis with absence of inflammatory changes indicating that repairing mechanisms and tissue remodeling had been taking place. This case report provides evidence for the hypothesis that micro-injuries induce repairing mechanisms and thus tissue remodeling which leads to consecutive tissue weakening and mechanical failure during a non-adequate trauma. Micro-injuries can occur during leisure activities and remain clinically invisible until rupture.

Osteotomias do processo coracoide: um estudo anatômico

OBJETIVO: Estudar as principais estruturas tendinosas e ligamentares inseridas no processo coracoide, correlacionando com diversos níveis de osteotomia e relatando as estruturas envolvidas no fragmento distai osteotomizado. MÉTODOS: Trinta ombros de 15 cadáveres (10 masculinos e cinco femininos) frescos foram dissecados. O processo coracoide com as principais estruturas anatômicas inseridas foram dissecados e cinco níveis de osteotomias (1,0; 1,5; 2,0; 2,5; 3,0cm) foram realizadas a partir do ápice e anotadas as principais estruturas inseridas no fragmento distal osteotomizado. RESULTADOS: Nas osteotomias de 1,0cm, em 100% dos casos houve envolvimento somente do tendão conjunto (TC). Nas osteotomias de 1,5cm, em 63,33% houve envolvimento do TC e peitoral menor (PMe), em 20% apenas do TC e em 16,66% do TC, PMi e ligamento coracoumeral (LCU). Nas osteotomias de 2,0cm, em 80% dos ombros, as osteotomias abrangeram o TC, PMe e o LCU e em 20% houve apenas envolvimento de TC e PMe. Nas osteotomias de 2,5cm, em 100% dos casos houve envolvimento do TC, PMe e LCU. Nas osteotomias de 3,0cm, em seis casos (20%) houve lesão do ligamento trapezoide e em 100% destas osteotomias, o fragmento distal osteotomizado abrangia o TC, PMe, LCU e em 90% envolvia também totalmente o ligamento coracoacromial. CONCLUSÃO: O conhecimento das estruturas anatômicas inseridas e envolvidas nos cortes das osteotomias do processo coracoide é de fundamental importância no manejo das osteotomias realizadas nas técnicas que utilizam o processo coracoide como enxerto ou referência anatômica. Nas osteotomias de 3,0cm há o risco de lesão do ligamento trapezoide.

Biomechanical investigation of the stabilization principle of the Latarjet procedure

The purpose of the study was to determine the biomechanical status of the different components of the Latarjet procedure. The anterior capsule reconstruction with the transferred coracoacromial ligament (CAL) and the necessity of an intact subscapularis tendon were of particular interest. We hypothesized that the anterior capsule reconstruction will have a significant effect and that the Latarjet procedure will lose its stabilizing effect if the subscapularis tendon is torn. Stability testing of 12 human shoulder specimens was performed. After testing of the intact joint, a combined anterior glenoid and capsule defect was set arthroscopically. Then the Latarjet procedure was performed using an open approach and tested with and without loading of the conjoint tendons (10N). Afterwards, the specimens were distributed into two groups and the Latarjet technique was reduced stepwise: dissection of the CAL, dissection of the conjoint tendons (group A); reduction of the coracoid segment, dissection of the subscapularis tendon (group B). Biomechanical testing was performed for each condition in two positions: 60° of glenohumeral abduction with neutral rotation and with 60° of external rotation; each with a passive humerus load of 30N in the anterior, inferior and anteroinferior direction. The Latarjet technique with load applied to the conjoint tendons significantly reduced translation compared with the defect condition for all tested positions in all directions. In group A, the CAL-dissection led to a significant increase of anterior translation (+5.0mm, p=0.003) and inferior translation (+7.3mm, p=0.025) in neutral rotation and of anterior translation in 60° of external rotation (+4.4mm, p=0.034). In group B, the reduction of the coracoid bone down to the coracoid tip resulted in a significant increase of only the anterior translation in abduction and 60° of external rotation (+4.5mm, p=0.05). In contrast, the detachment of the subscapularis tendon led to a significant increase of translation in all testing positions except the inferior direction in the neutral rotation. We found the anterior capsule reconstruction to represent a significant contribution to the stabilizing effect of the Latarjet procedure, whereas a deficiency of the subscapularis tendon eliminates its effect. We recommend to perform the Latarjet technique with an anterior capsule reconstruction (e.g. CAL transfer) and with a transfer of the coracoid bone block rather than a transposition of the coracoid tip. Furthermore, we were able to show that an intact subscapularis tendon is a necessary prerequisite for a reliable stabilization.

Evaluation and Imaging of an Untreated Grade III Hamstring Tear: A Case Report

Muscle strains are one of the most common complaints treated by physicians. High-force lengthening contractions can produce very high forces resulting in pain and tissue damage; such strains are the most common cause of muscle injuries. The hamstring muscles are particularly susceptible as they cross two joints and regularly perform lengthening contractions during running. We describe a patient with return to full function after a large hamstring tear. We report the case of a 26-year-old man who presented 1 year after a noncontact, left-sided proximal hamstring tear incurred while sprinting. He received no medical treatment or formal rehabilitation. He was able to return to all sports and activities 1 to 2 months after injury, but noted a persistent deformity of the proximal thigh, which led him to seek evaluation. Physical examination, MRI functional tests, and specific muscle tests 1 year after his injury documented a major hamstring tear at the musculotendinous junction with muscle retraction, but no avulsion of the proximal tendon attachment. Surgery often is recommended for major proximal hamstring tendon tears, especially when more than one tendon of origin is ruptured from the ischial tuberosity. Myotendinous tears are treated nonoperatively, but may be associated with decreased strength, prolonged recovery, and recurrence. We describe the case of a young man who sustained a hamstring tear, with retraction, at the proximal myotendinous junction, where the biceps femoris and semitendinosus arise from the conjoint tendon. He achieved full functional recovery without medical attention, but had a persistent cosmetic deformity and slight hamstring tightness. This case suggests a benign natural history for this injury and the appropriateness of noninvasive treatment.

Magnetic resonance imaging-controlled results of the pectoralis major tendon transfer for irreparable anterosuperior rotator cuff tears performed with standard and modified fixation techniques

Irreparable ruptures of the subscapularis tendon lead to impaired function of the shoulder joint. In such cases, transfer of the pectoralis major tendon has led to encouraging results. The procedure fails periodically, typically associated with insufficient in-growth of the transferred tissue. We hypothesized that tendon harvest with chips of cancellous bone would improve the tendon-bone interface. Of 62 consecutive pectoralis tendon transfers, 54 shoulders were followed-up at an average of 35 months. In all shoulders, the transferred tendon was rerouted behind the conjoint tendon and fixed by transosseous sutures. In 29 shoulders, the tendon was harvested with a cuff of cancellous bone. In 25 shoulders, the conventional technique with sharp detachment of the tendon was used. Apart from detailed clinical examination of all shoulders, a magnetic resonance image (MRI) was available in 52 shoulders. The overall Constant score had improved from an average of 38.8 points preoperatively to 63.4 points at follow-up. Shoulders treated with the new fixation technique scored 64.4 compared with 62.2 for the conventional fixations. The MRI showed intact tendons and muscles in 80.8% of shoulders. In 7 shoulders (13.5%), the transferred tendon was ruptured. Two of these were treated with the new fixation technique. Mean patient satisfaction score was 8.2 points. A secure method of fixation that avoids secondary ruptures despite insufficiency of the transferred tendon is of great importance. Also the rerouting of the transferred tendon under the conjoined tendon is essential to imitate the natural force vector and the function of an intact subscapularis tendon. Patients in this investigation were also monitored by MRI to verify the integrity of the transferred tendon. As a salvage procedure, the pectoralis major tendon transfer provides good results in most cases. Sufficient in-growth of the transferred tissue is essential for the success of the procedure. This seems to be facilitated by both methods.

Arthroscopic Coracoid Transposition for Recurrent Shoulder Anterior Instability. An Operative Technique

We report a technique of an arthroscopic concomitant Bankart repair with a transfer of the coracoid bone block and conjoint tendons for revision anterior shoulder instability. The operative procedure consists of an arthroscopic transfer of the conjoined tendon with a coracoid and arthroscopic Bankart repair. First, a typical Bankart suture anchor procedure with two suture anchors was performed into the antero-inferior part of the glenoid rim. After, tenodesis of the coraco-biceps tendon was performed in the middle of the subscapularis tendon fixing the coracoid bony fragment into a glenoid socket with a bioabsorbable interference screw. This operative technique is an alternative in the treatment of revision anterior shoulder instability in patients with deficient anterior capsule.

Sports hernia—What is it and what can be done?

Sports hernia is a component of a more severe injury known as footballer's groin or groin disruption injury which consists of: sports (occult) hernia; conjoint tendon tear; adductor tendinopathy; obturator nerve entrapment; osteitis pubis. A sports hernia occurs through torn muscle fibres of the Internal oblique and Transversus abdominis medial to the inferior epigastric vessels in Hesselbach's triangle of the inguinal (groin) canal of the lower abdomen. The presenting symptom is groin pain, discomfort, ache or lower abdominal pain without a visible or palpable hernia.

Anatomy of piriformis, obturator internus and obturator externus

We dissected 20 cadaver hips in order to investigate the anatomy and excursion of the trochanteric muscles in relation to the posterior approach for total hip replacement. String models of each muscle were created and their excursion measured while the femur was moved between its anatomical position and the dislocated position. The position of the hip was determined by computer navigation. In contrast to previous studies which showed a separate insertion of piriformis and obturator internus, our findings indicated that piriformis inserted onto the superior and anterior margins of the greater trochanter through a conjoint tendon with obturator internus, and had connections to gluteus medius posteriorly. Division of these connections allowed lateral mobilisation of gluteus medius with minimal retraction. Analysis of the excursion of these muscles revealed that positioning the thigh for preparation of the femur through this approach elongated piriformis to a maximum of 182%, obturator internus to 185% and obturator externus to 220% of their resting lengths, which are above the thresholds for rupture of these muscles. Our findings suggested that gluteus medius may be protected from overstretching by release of its connection with the conjoint tendon. In addition, failure to detach piriformis or the obturators during a posterior approach for total hip replacement could potentially produce damage to these muscles because of over-stretching, obturator externus being the most vulnerable.

Preoperative progressive pneumoperitoneum for giant inguinal hernias

Reduction of giant hernia contents into the abdominal cavity may cause intraoperative and postoperative problems such as abdominal compartment syndrome. Preoperative progressive pneumoperitoneum expands the abdominal cavity, increases the patient’s tolerability to operation, and can diminish intraoperative and postoperative complications. Preoperative progressive pneumoperitoneum is recommended for giant ventral hernias, but rarely for giant inguinal hernias. We present two giant inguinal hernia patients who were prepared for hernia repair with preoperative progressive pneumoperitoneum and then treated successfully by graft hernioplasty. We observed that abdominal expansion correlated with the inflated volume and pressure during the first four days of pneumperitoneum. Although insufflated gas volume can be different among patients, we observed that the duration of insufflation may be the same for similar patients.

Histology of the internal inguinal ring: it is really a novelty?

We have read with great interest the article published by Amato et al. regarding their histopathological findings of the internal inguinal ring in patients having indirect inguinal hernia [1]. Although we consider this article not only interesting but also important to comprehend the morphological changes of inguinal hernia, we have some considerations and comments regarding this subject and, particularly, this report. After careful analysis and discussion over the microphotographs published in the article of Amato et al., we failed to identify the so called ‘‘diffuse fibrohyaline degeneration within the muscle fibers of the internal inguinal ring’’ [1]. Moreover, the microphotographs included in the article did not show any muscle fibers. The images corresponded to a fascial fibrous structure corresponding to the specialized connective tissue, characteristic of the transversalis fascia, which, at the level of the internal inguinal ring, becomes thicker [2, 3]. A marked attenuation of the transversalis fascia and significant reduction in thickness of connective tissue in the area of the internal inguinal ring has been previously described in patients with indirect inguinal hernias [2], this abnormality being caused by collagen disorders [4]. Regardless that the article of Amato et al. is an original report on the histology of the internal inguinal ring, it is no less true that, for many years, it has been known that the internal inguinal ring is an opening in the transversalis fascia [2, 3, 5]. This opening is thick at the edges of the inguinal ring, which is surrounded by fibrous fascial fibers from the conjoint tendon and muscular fibers from the internal oblique muscle [3, 5]. The lower fibers of the internal oblique muscle have their origin at the Poupart’s ligament and curve upward, inward, and downward to form the conjoint tendon. Contraction of these fibers approximates the muscle edge and Poupart’s ligament, reinforcing the internal ring against increased intra-abdominal pressure [3]. Consequently, if Amato et al. claimed to have taken biopsy samples from the ‘‘muscular tissue from the upper border of the inguinal ring’’ [1], they meant that the tissue samples they aimed to take corresponded to muscular fibers from the internal oblique muscle, which originate, in part, from the Poupart’s ligament covering the internal inguinal ring [3, 5]. Nonetheless, they did not show any muscular fibers in their microphotographs. Regarding the inflammatory response they claimed to have observed, a careful examination of their microphotographs failed to show an important lymphohistiocytary infiltration. Moreover, the venous congestion they described corresponded to the normal tissue response to surgical injury, which is an expected phenomenon. Regarding the nerve endings found in tissue samples, they are also expected because they regulate the sphincter-like function of the conjoint tendon acting over the internal inguinal ring. C. Barria Histomed, La Serena, Chile

Functional anatomy of the Achilles tendon

The Achilles tendon is the strongest and thickest tendon in the human body. It is also the commonest tendon to rupture. It begins near the middle of the calf and is the conjoint tendon of the gastrocnemius and soleus muscles. The relative contribution of the two muscles to the tendon varies. Spiralisation of the fibres of the tendon produces an area of concentrated stress and confers a mechanical advantage. The calcaneal insertion is specialised and designed to aid the dissipation of stress from the tendon to the calcaneum. The insertion is crescent shaped and has significant medial and lateral projections. The blood supply of the tendon is from the musculotendinous junction, vessels in surrounding connective tissue and the osteotendinous junction. The vascular territories can be classified simply in three, with the midsection supplied by the peroneal artery, and the proximal and distal sections supplied by the posterior tibial artery. This leaves a relatively hypovascular area in the mid-portion of the tendon where most problems occur. The Achilles tendon derives its innervation from the sural nerve with a smaller supply from the tibial nerve. Tenocytes produce type I collagen and form 90% of the cellular component of the normal tendon. Evidence suggests ruptured or pathological tendon produce more type III collagen, which may affect the tensile strength of the tendon. Direct measurements of forces reveal loading in the Achilles tendon as high as 9 KN during running, which is up to 12.5 times body weight.

Sportsman hernia: what can we do?

Sportsman (sports) hernia is a medially located bulge in the posterior wall of the inguinal canal that is common in football players. About 90% of cases occur in males. The injury is also found in the general population. The presenting symptom is chronic groin pain which develops during exercise, aggravated by sudden movements, accompanied by subtle physical examination findings and a medial inguinal bulge on ultrasound. Pain persists after a game, abates during a period of lay-off, but returns on the resumption of sport. Frequently, sports hernia is one component of a more extensive pattern of injury known as 'groin disruption injury' consisting of osteitis pubis, conjoint tendinopathy, adductor tendinopathy and obturator nerve entrapment. Certain risk factors have been identified, including reduced hip range of motion and poor muscle balance around the pelvis, limb length discrepancy and pelvic instability. The suggested aetiology of the injury is repetitive athletic loading of the symphysis pubis disc, leading to accelerated disc degeneration with consequent pelvic instability and vulnerability to micro-fracturing along the pubic osteochondral junction, periosteal stripping of the pubic ligaments and para-symphyseal tendon tears, causing tendon dysfunction. RADIOLOGY: Diagnostic imaging includes an erect pelvic radiograph (X-ray) with flamingo stress views of the symphysis pubis, real-time ultrasound and, occasionally, computed tomography (CT) scanning and magnetic resonance imaging (MRI), but seldom contrast herniography. Other imaging tests occasionally performed can include nuclear bone scan, limb leg measurement and test injections of local anaesthetic/corticosteroid. PREVENTION AND TREATMENT: The injury may be prevented by the detection and monitoring of players at risk and by correcting significant limb length inequality. Groin reconstruction operation consists of a Maloney darn hernia repair technique, repair of the conjoint tendon, transverse adductor tenotomy and obturator nerve release. Rehabilitation involves core stabilisation exercises and the maintenance of muscle control and strength around the pelvis. Using this regimen of groin reconstruction and post-operative rehabilitation, a player would be anticipated to return to their pre-injury level of activity approximately 3 months after surgery.

Rupture of the conjoint tendon at the proximal musculotendinous junction of the biceps femoris long head: a case report

This case report describes a 20-year-old elite-level Australian Rules football player who suffered three unilateral hamstring injuries within a 2 month period. The first two episodes were managed conservatively. Magnetic resonance imaging following the third episode revealed full thickness disruption of the proximal musculotendinous junction of the biceps femoris long head and semitendinosus muscles and the common proximal (conjoint) tendon. The injury was subsequently surgically repaired. At 16 months following surgery, the player had successfully completed a full competitive season of elite-level Australian Rules football symptom free. Follow-up magnetic resonance imaging demonstrated the repaired tendon to be uniformly hypointense in keeping with reparative granulation tissue formation and restoration of normal muscle morphology. These findings are consistent with an intact repair. The case demonstrates that complete functional and radiological resolution is possible following surgical repair of significant hamstring musculotendinous junction tears.

Pectoralis Major Tendon Transfers Above or Underneath the Conjoint Tendon in Subscapularis-Deficient Shoulders

Background: Different operative techniques for transfer of the pectoralis major tendon have been proposed for the treatment of irreparable ruptures of the subscapularis tendon. The objective of this study was to compare the effects of two techniques of transferring the pectoralis major tendon (above or underneath the conjoint tendon) on glenohumeral kinematics during active abduction in a biomechanical model of a subscapularis-deficient shoulder. Methods: Six shoulder specimens were tested with a custom dynamic shoulder testing apparatus. After the kinematics of the intact shoulder were recorded, a complete tear of the subscapularis tendon was simulated surgically. A transfer of the clavicular portion of the pectoralis major muscle to the lesser tuberosity was then performed with the transferred tendon placed either above (tendon-transfer 1) or underneath (tendon-transfer 2) the conjoint tendon. For each condition, the maximum abduction angle as well as the external rotation angle and the superoinferior and anteroposterior humeral translations at the maximum abduction angle were recorded. Results: With the rotator cuff intact, the mean maximum glenohumeral abduction angle (and standard error of the mean) was 86.3° ± 2.1° and the mean amount of external rotation at the maximum abduction angle was 5.5° ± 7.6°. A complete tear of the subscapularis tendon decreased the mean maximum abduction angle to 40.8° ± 2.4° (p < 0.001) and increased the mean external rotation to 91.8° ± 4.8° (p < 0.001). The mean humeral translations in the anterior and superior directions (+3.4 ± 0.5 and +6.3 ± 0.3 mm, respectively) at the maximum abduction angle were also increased (p < 0.01 and p < 0.001) when compared with those in the intact shoulder. Significant differences were found in the mean maximum abduction angle as well as the mean external rotation angle and humeral translations (anterior and superior) at maximum abduction between the tendon-transfer-1 condition (63.2° ± 13.5°, 82.4° ± 6.6°, 4.0 ± 1.8 mm, and 3.3 ± 1.9 mm, respectively) and tendon-transfer-2 condition (89.5° ± 12.3°, 45.7° ± 22.5°, –0.6 ± 2.0 mm, and 0.5 ± 2.3 mm, respectively). The tendon-transfer-2 condition restored glenohumeral kinematics that were closer to those in the intact shoulder than were those resulting from the tendon-transfer-1 condition. Conclusions: Transfer of the pectoralis major tendon in subscapularis-deficient shoulders partially restored the glenohumeral kinematics of the intact shoulder. One possible explanation for the superior effect of the tendon-transfer-2 condition is that, with a pectoralis major tendon transfer underneath the conjoint tendon, the line of action of the transferred tendon is closer to that of the subscapularis muscle. Clinical Relevance: From a biomechanical standpoint, it may be preferable to perform a pectoralis major tendon transfer underneath the conjoint tendon in subscapularis-deficient shoulders.

Pectoralis Major Tendon Transfers Above or Underneath the Conjoint Tendon in Subscapularis-Deficient Shoulders

Different operative techniques for transfer of the pectoralis major tendon have been proposed for the treatment of irreparable ruptures of the subscapularis tendon. The objective of this study was to compare the effects of two techniques of transferring the pectoralis major tendon (above or underneath the conjoint tendon) on glenohumeral kinematics during active abduction in a biomechanical model of a subscapularis-deficient shoulder. Six shoulder specimens were tested with a custom dynamic shoulder testing apparatus. After the kinematics of the intact shoulder were recorded, a complete tear of the subscapularis tendon was simulated surgically. A transfer of the clavicular portion of the pectoralis major muscle to the lesser tuberosity was then performed with the transferred tendon placed either above (tendon-transfer 1) or underneath (tendon-transfer 2) the conjoint tendon. For each condition, the maximum abduction angle as well as the external rotation angle and the superoinferior and anteroposterior humeral translations at the maximum abduction angle were recorded. With the rotator cuff intact, the mean maximum glenohumeral abduction angle (and standard error of the mean) was 86.3 degrees +/- 2.1 degrees and the mean amount of external rotation at the maximum abduction angle was 5.5 degrees +/- 7.6 degrees . A complete tear of the subscapularis tendon decreased the mean maximum abduction angle to 40.8 degrees +/- 2.4 degrees (p < 0.001) and increased the mean external rotation to 91.8 degrees +/- 4.8 degrees (p < 0.001). The mean humeral translations in the anterior and superior directions (+3.4 +/- 0.5 and +6.3 +/- 0.3 mm, respectively) at the maximum abduction angle were also increased (p < 0.01 and p < 0.001) when compared with those in the intact shoulder. Significant differences were found in the mean maximum abduction angle as well as the mean external rotation angle and humeral translations (anterior and superior) at maximum abduction between the tendon-transfer-1 condition (63.2 degrees +/- 13.5 degrees , 82.4 degrees +/- 6.6 degrees , 4.0 +/- 1.8 mm, and 3.3 +/- 1.9 mm, respectively) and tendon-transfer-2 condition (89.5 degrees +/- 12.3 degrees , 45.7 degrees +/- 22.5 degrees , -0.6 +/- 2.0 mm, and 0.5 +/- 2.3 mm, respectively). The tendon-transfer-2 condition restored glenohumeral kinematics that were closer to those in the intact shoulder than were those resulting from the tendon-transfer-1 condition. Transfer of the pectoralis major tendon in subscapularis-deficient shoulders partially restored the glenohumeral kinematics of the intact shoulder. One possible explanation for the superior effect of the tendon-transfer-2 condition is that, with a pectoralis major tendon transfer underneath the conjoint tendon, the line of action of the transferred tendon is closer to that of the subscapularis muscle.

Radiologic Anatomy of the Inguinofemoral Region: Insights from MDCT

We set out to reexamine the radiologic anatomy of the inguinofemoral region using volume data sets obtained with an MDCT scanner. We conducted a systematic prospective review of CT scans of 20 consecutively enrolled patients, 10 men and 10 women chosen retrospectively from our CT database. An experienced radiologist and a senior trainee surgeon conducted an image review to maximize recognition of relevant anatomic detail. The inferior epigastric artery and femoral canal were identified in all planes in all patients. On axial views a spur on the pubic bone was visible in 17 (85%) of the patients, but the inguinal ligament was not reliably identified in any. The round ligament or spermatic cord was visible in only 15 (75%) of 20 patients. In contrast, on coronal and sagittal views, the inguinal ligament, which is vital to reliable identification and accurate classification of groin hernias, was visible in 19 (95%) of the 20 patients. Scans in the sagittal plane best depicted the gutter-like aspect of the ligament, the canal and contents being clearly visible in 95% of the patients. On sagittal views, the internal ring was identifiable in 90% and the round ligament or spermatic cord in 95% of the patients. On coronal images, the internal ring was identified in all and the conjoint tendon in 95% of the patients. The round ligament or spermatic cord was not seen in 10% of the patients. MDCT produces images of the inguinal region in detail not possible with previous generations of scanners. In our small series, 100% identification of key anatomic structures was achieved when information from all three views was combined. We found subtle differences between imaging findings and standard anatomic teaching.

Biceps Transfer Using Subdeltoid Arthroscopy

| ABSTRACT The diagnosis and treatment of biceps tendon pathology remain controversial. These patients may be more resistant to conservative treatment than those patients with standard subacromial impingement. When conser- vative treatment fails, surgical options should be explored. Tenotomy and tenodesis of the biceps tendon have been described, although persistent pain, deform- ity, and muscle cramping have been frequently reported. We describe a novel technique of biceps tenodesis by arthroscopic transfer of the long head of the biceps tendon to the anterior aspect of the lateral conjoint tendon using the subdeltoid space. The soft tissue transfer closely reproduces the native axis of pull of the biceps. It also allows soft tissue healing, which creates the normal ''bungee^ effect of the superior labrum/biceps anchor complex. This technique also allows the surgeon direct visualization during tenodesis to help prevent overtensioning of the tendon. Because of the early success of the procedure, we continue to use this technique with increasing frequency in appropriately indicated patients to access the anterior aspect of the shoulder extraarticularly.

Arthroscopic Subdeltoid Approach to the Biceps Transfer

Arthroscopy is an accepted tool in the treatment of many types of shoulder pathology. The arthroscopic subdeltoid approach consists of the posterior–portal-based arthroscope being advanced into the subdeltoid space via the subacromial space, then exposure of the space with shaving or radiofrequency ablation. The other portals are then made with a spinal needle localization piercing the anterior deltoid. This subdeltoid approach is well-suited to problems such as pectoralis major and subscapularis muscle tear, as well as massive rotator cuff tear repairs, problems that were previously difficult to address from the standard arthroscopic portals. This approach also allows transfer of the biceps tendon to the conjoint tendon. When patients continue to be symptomatic despite conservative interventions, surgical options need to be explored. Currently, there is no gold standard for the surgical treatment of biceps tendon pathology. Some authors favor tenodesis whereas others advocate tenotomy or transfer. Many of the treatments, including tenodesis and tenotomy, have had excellent rates of success, but complications, such as deformity, persist. We describe a new arthroscopic technique for biceps tenodesis via transfer of the long head of the biceps tendon to the conjoint tendon using the subdeltoid space. With this technique, the tendons are under direct visualization for proper tensioning, and the transferred tendon is approximately in the same orientation as in its native location. In the appropriately indicated patient, this technique may yield relief from biceps specific symptoms.