Hyperconcavity of the lumbar vertebral endplates in the elite football lineman.

BACKGROUND: Hyperconcavity of the vertebral endplates is a previously unreported radiologic phenomenon. PURPOSE: To analyze hyperconcavity of the vertebral endplates with expansion of the disk space in pre-National Football League lineman and to determine its clinical significance. STUDY DESIGN: Descriptive anatomical study. METHODS: Over a 2-year period (1992-1993), 266 elite football linemen were evaluated at the National Football League scouting combine held in Indianapolis, Indiana. Evaluation focused on the lumbosacral spine and included history, physical examination, and lateral radiographs. Measurements were taken of all the vertebral endplate defects of involved vertebrae and compared with an age-matched control group of 110 patients. RESULTS: The analyzed data revealed the following: (1) hyperconcavity of the vertebral endplates appeared as a distinct entity in a high percentage of pre-National Football League lineman (33%) compared with age-matched controls (8%), (2) there was a trend toward a lower incidence of lumbosacral spine symptoms in those players who displayed hyperconcavity of the vertebral endplates (16%) versus those who did not (25%), and (3) when hyperconcavity of the vertebral endplates was present, all 5 lumbosacral disk spaces were commonly affected. CONCLUSIONS: Hyperconcavity of the vertebral endplates and hypertrophy of the disk space are likely adaptive changes occurring over time in response to the repetitive high loading and axial stress experienced in football line play.

A biomechanical comparison of suture constructs used for coracoclavicular fixation.

There is no consensus regarding surgical treatment for severely dislocated acromioclavicular joints. Although many treatments are suture-based, the suture materials and resulting suture-bone constructs have been subjected to limited systematic evaluation. This study identifies the strongest and least deforming suture construct among those commonly used for such repairs. Each suture-based repair was tested on a simulated clavicle and coracoid process with the skeletal components distracted until the suture failed to obtain tensile strength. Additional groups of sutures were subjected to cyclic loading to determine resistance to deformation. Panacryl braid had significantly greater tensile strength than all other constructs: Polydioxanone (PDS) braid, Mersilene tape, and Ethibond #5. Deformation after cyclic loading of Panacryl braid, PDS braid, and two strands of Mersilene tape was significantly less than that of the other constructs. A bioabsorbable suture loop, such as Panacryl, can act as a temporary internal splint, maintaining acromioclavicular joint reduction long enough for ligamentous healing during rehabilitation, and can avoid complications associated with permanent fixation materials. Panacryl braid deserves serious consideration for coracoclavicular fixation because of its strength, resistance to deformation, and bioabsorbable properties.

Thermal capsulorraphy of bilateral glenohumeral joints in a pediatric patient with Ehlers-Danlos syndrome.

Ehlers-Danlos syndrome (EDS) is a heterogeneous collection of inherited connective tissue disorders characterized by hypermobility of the joints and hyperextensibility and fragility of the skin. For many patients, the hypermobile joints become problematic. To date, the mainstay of surgical treatment for EDS-related joint laxity has been open surgical capsulorraphy, which, although usually effective, confers significant morbidity to the patient. We present the case of a 9-year-old girl diagnosed with a variant of EDS and severely disabled from multidirectional instability of her shoulders and recurrent dislocations of her hips. After 1 year of nonoperative treatment (physical therapy, bracing, and activity restriction) failed, we performed a sequential arthroscopic thermal capsulorraphy of both shoulders. At a 2-year follow-up, the patient has no instability in the left shoulder and only occasional subluxations of the contralateral shoulder. We believe that thermal capsulorraphy is a viable addition to the shoulder surgeon's armamentarium in treating multidirectional instability in children with EDS.

Radiographic findings associated with symptomatic rotator cuff tears.

This study compared shoulder radiographs of patients with a documented rotator cuff tear with those of asymptomatic age-matched controls. Radiographs of 40 subjects with documented rotator cuff tears were evaluated along with similar films of 84 asymptomatic age-matched controls. Three radiographs were taken of each shoulder: (1) acromioclavicular joint view, (2) anterior-posterior view with 30 degrees of external rotation, and (3) supraspinatus outlet view. Two fellowship-trained radiologists interpreted 14 radiographic areas in a blinded fashion. Inspection of the greater tuberosity showed large positive abnormal ratings for sclerosis, osteophytes, subchondral cysts, and osteolysis. No association was noted between acromial morphology and rotator cuff tears. These results indicate that shoulder radiographs of subjects with a documented rotator cuff tear have greater tuberosity radiographic abnormalities that are not noted in asymptomatic subjects without a rotator cuff tear. No relationship was found between tear length and any of the degenerative conditions.

Analysis of rotator cuff muscles in adult human cadaveric specimens.

Management of irreparable massive rotator cuff tears remains a challenging and controversial problem. Defining glenohumeral force relations may allow for the development of treatment strategies based on biomechanical principles. Five fresh-frozen adult human cadaveric shoulder specimens were dissected to determine fiber length, mass, and lever arm of (a) the 3 bellies of the deltoid and (b) the rotator cuff muscles (supraspinatus, infraspinatus, teres minor, subscapularis). From these data, physiologic cross-sectional areas and moment relations were calculated. These relations provide evidence for a balanced axial force couple between the anterior and posterior rotator cuff. Demonstration of an axial force couple across the glenohumeral joint may have clinical significance for treatment of irreparable massive rotator cuff tears and may explain why many patients with full-thickness rotator cuff tears can regain acceptable shoulder function.

An arthroscopic technique for confirming intra-articular subluxation of the long head of the biceps tendon: the ramp test.

The purpose of this technical note is to introduce the ramp test and explain this arthroscopic technique. The ramp test is used to test the integrity of the soft tissue restraint to intra-articular subluxation of the long head of the biceps tendon. Injury to the soft tissue restraint, the hidden lesion, has been proposed as occurring in conjunction with a full-thickness rotator cuff tear. Both cadaveric dissections and arthroscopic patient assessments were conducted to develop the ramp test. In this study, 17 patients also presented with refractory anterior shoulder pain and underwent arthroscopy to further characterize the ramp test. An abnormal examination result showed that the long head of the biceps tendon translated medially and inferiorly across the humeral head. In addition, this subgroup of 17 patients all had an abnormal ramp test but did not have a full-thickness rotator cuff tear. The ramp test is now applied to all arthroscopic procedures by the senior author, and we recommend its use for arthroscopic confirmation of intra-articular subluxation of the long head of the biceps tendon. Thus, we advocate that an abnormal ramp test result indicates pathology and warrants the surgical removal of the long head of the biceps tendon from the glenohumeral joint.

The effect of continuous cryotherapy on glenohumeral joint and subacromial space temperatures in the postoperative shoulder.

PURPOSE: The objective of this investigation was to determine the effect of continuous cryotherapy on glenohumeral joint and subacromial space temperatures in the postoperative shoulder. TYPE OF STUDY: Prospective, randomized, and controlled clinical trial. METHODS: Twenty patients (10 cryotherapy, 10 controls) with a full-thickness rotator cuff repair were monitored with temperature sensors in the glenohumeral joint and subacromial space of the shoulder for 23 postoperative hours. Statistical analysis (P <.05) was performed using the Mann-Whitney rank-sum test. RESULTS: In comparing the cryotherapy and control groups, analysis of the glenohumeral joint and subacromial space temperatures revealed a statistical significance at 4, 8, and 23, and 4, 8, 16, and 20 postoperative hours, respectively. In addition, a trend toward a temperature-rising phase occurs from 4 to 12 hours and is followed by a trend toward a thermostatic phase from 12 to 23 hours during which temperatures remain relatively constant. The subacromial space was consistently cooler than the glenohumeral joint by an interval between 0.07 degrees C to 0.50 degrees C except at 23 hours postoperative where the glenohumeral joint was 0.05 degrees C cooler. CONCLUSIONS: Continuous cryotherapy causes a statistically significant reduction of both glenohumeral joint and subacromial space temperatures in the shoulder at variable times during the first 23 postoperative hours. Previous investigations have shown that minor elevations in intra-articular temperature can stimulate proteolytic enzyme activity, which has detrimental effects on articular cartilage. Previous research has also shown that cryotherapy is an effective nonpharmacological method of pain control. Yet the literature has assumed that the effects of cryotherapy are part of the basic analgesia mechanism because of a reduction in joint temperature. Our results affirm that reductions in glenohumeral joint and subacromial space temperatures in the postoperative shoulder do occur, leading to potential benefits of continuous cryotherapy as an effective mode of pain control in the postoperative care of patients.

The cosmetic appearance of the biceps muscle after long-head tenotomy versus tenodesis.

PURPOSE: This study evaluates the cosmetic appearance of the biceps muscle after arthroscopic, intra-articular biceps tenotomy versus tenodesis by presenting subjective outcome results in patients with refractive bicipital pain. TYPE OF STUDY: Retrospective study evaluating clinical follow-up of patients with refractive and chronic bicipital pain. METHODS: Five consecutive years of patients receiving biceps tenotomy (80 patients; 40 males, 40 females; average age, 58 years) or tenodesis (80 patients; 51 males, 29 females; average age, 54 years) procedures were retrospectively followed-up by grading anterior shoulder pain, muscle spasms in the biceps, and cosmetic deformity of the biceps muscle. Statistics were done by chi(2) analysis. RESULTS: When assessing the follow-up questions, no statistical significance was found between the biceps tenotomy and biceps tenodesis groups. There was also no statistical significance when comparing the biceps tenotomy and biceps tenodesis groups when evaluating only the men, women, and men versus women with respect to the questions assessed. CONCLUSIONS: In the majority of patients in which a biceps tenotomy is performed, we note that the cosmetic appearance of the biceps muscle, the grade of muscle spasms of the biceps, and the level of anterior shoulder pain would present with little difference than if a tenodesis had been performed. Therefore, a biceps tenotomy may be a reasonable alternative to a biceps tenodesis in patients with refractive and chronic bicipital pain.

Retroversion of the humerus in the throwing shoulder of college baseball pitchers.

BACKGROUND: Increased external rotation and decreased internal rotation have been noted to occur progressively in the throwing shoulder of baseball pitchers. HYPOTHESIS: Proximal remodeling of the humerus contributes to the rotational asymmetry between shoulders in pitchers. STUDY DESIGN: Descriptive anatomic study. METHODS: Both shoulders of 19 male college baseball pitchers were evaluated and retroversion of the humerus calculated by using the technique of Söderlund et al. Measurements were taken of passive glenohumeral external rotation at 0 degrees and 90 degrees of abduction and internal rotation at 90 degrees of abduction under a 3.5-kg load. Subjects completed a questionnaire on the amount and duration of overhead throwing performed during the ages 8 through 16 years. RESULTS: All of the subjects had greater external rotation at 0 degrees and 90 degrees of abduction, decreased internal rotation at 90 degrees of abduction, and greater retroversion of the humerus in their dominant compared with nondominant shoulders. A significant difference was found between dominant and nondominant external rotation at 0 degrees and 90 degrees of abduction, internal rotation at 90 degrees of abduction, and retroversion of the humerus. In the dominant arm, there was a significant correlation between retroversion of the humerus and external rotation at 0 degrees and 90 degrees of abduction. There was also a significant correlation between the side-to-side difference in retroversion of the humerus compared with the side-to-side difference in external rotation at 90 degrees of abduction. CONCLUSIONS: Rotational changes in the throwing shoulder are due to bony as well as soft tissue adaptations.

An electromyographic analysis of sumo and conventional style deadlifts.

PURPOSE: Strength athletes often employ the deadlift in their training or rehabilitation regimens. The purpose of this study was to compare muscle activity between sumo and conventional style deadlifts, and between belt and no-belt conditions. METHODS: Six cameras collected 60-Hz video data and 960-Hz electromyographic data from 13 collegiate football players who performed sumo and conventional deadlifts with and without a lifting belt, employing a 12-RM intensity. Variables measured were knee angles and EMG measurements from 16 muscles. Muscle activity were averaged and compared within three 30-degree knee angle intervals from 90 to 0 degrees during the ascent, and three 30-degree knee angle intervals from 0 to 90 degrees during the descent. RESULTS: Overall EMG activity from the vastus medialis, vastus lateralis, and tibialis anterior were significantly greater in the sumo deadlift, whereas overall EMG activity from the medial gastrocnemius was significantly greater in the conventional deadlift. Compared with the no-belt condition, the belt condition produced significantly greater rectus abdominis activity and significantly less external oblique activity. For most muscles, EMG activity was significantly greater in the knee extending intervals compared with the corresponding knee flexing intervals. Quadriceps, tibialis anterior, hip adductor, gluteus maximus, L3 and T12 paraspinal, and middle trapezius activity were significantly greater in higher knee flexion intervals compared with lower knee flexion intervals, whereas hamstrings, gastrocnemius, and upper trapezius activity were greater in lower knee flexion intervals compared with higher knee flexion intervals. CONCLUSIONS: Athletes may choose to employ either the sumo or conventional deadlift style, depending on which muscles are considered most important according to their training protocols. Moderate to high co-contractions from the quadriceps, hamstrings, and gastrocnemius imply that the deadlift may be an effective closed kinetic chain exercise for strength athletes to employ during knee rehabilitation.