Subacromial Decompression in Patients With Shoulder Impingement With an Intact Rotator Cuff: An Expert Consensus Statement Using the Modified Delphi Technique Comparing North American to European Shoulder Surgeons

PURPOSE

To perform a Delphi consensus for the treatment of patients with shoulder impingement with intact rotator cuff tendons, comparing North American with European shoulder surgeon preferences.

METHODS

Nineteen surgeons from North America (North American panel [NAP]) and 18 surgeons from Europe (European panel [EP]) agreed to participate and answered 10 open-ended questions in rounds 1 and 2. The results of the first 2 rounds were used to develop a Likert-style questionnaire for round 3. If agreement at round 3 was ≤60% for an item, the results were carried forward into round 4. For round 4, the panel members outside consensus (>60%, <80%) were contacted and asked to review their response. The level of agreement and consensus was defined as 80%.

RESULTS

There was agreement on the following items: impingement is a clinical diagnosis; a combination of clinical tests should be used; other pain generators must be excluded; radiographs must be part of the workup; magnetic resonance imaging is helpful; the first line of treatment should always be physiotherapy; a corticosteroid injection is helpful in reducing symptoms; indication for surgery is failure of nonoperative treatment for a minimum of 6 months. The NAP was likely to routinely prescribe nonsteroidal anti-inflammatory drugs (NAP 89%; EP 35%) and consider steroids for impingement (NAP 89%; EP 65%).

CONCLUSIONS

Consensus was achieved for 16 of the 71 Likert items: impingement is a clinical diagnosis and a combination of clinical tests should be used. The first line of treatment should always be physiotherapy, and a corticosteroid injection can be helpful in reducing symptoms. The indication for surgery is failure of no-operative treatment for a minimum of 6 months. The panel also agreed that subacromial decompression is a good choice for shoulder impingement if there is evidence of mechanical impingement with pain not responding to nonsurgical measures.

LEVEL OF EVIDENCE

Level V, expert opinion.

Latissimus dorsi tendon transfer: a comparative analysis of primary and salvage reconstruction of massive, irreparable rotator cuff tears

On the basis of a modified Constant scoring system, we compared outcomes for 16 patients who underwent latissimus dorsi transfer as a salvage reconstruction for a failed prior rotator cuff repair with outcomes for 6 patients who underwent a primary reconstruction for an irreparable cuff defect. There was a statistically significant difference in Constant score between groups, which measured 55% for the salvage group compared with 70% for the primary group (P <.05). Poor tendon quality, stage 4 muscle fatty degeneration, and detachment of the deltoid insertion each had a statistically significant effect on the Constant score (P <.05). Late rupture of the tendon transfer occurred in 44% of patients in the salvage group compared with 17% in the primary group at a mean of 19 months postoperatively. Rupture had a statistically significant effect on the Constant score, which declined by a mean of 14% (P <.05). We conclude that salvage reconstruction of failed prior rotator cuff repairs yields more limited gains in satisfaction and function than primary latissimus dorsi transfer.

Comparison of results of percutaneous balloon mitral commissurotomy in patients aged > or = 65 years with those in patients aged < 65 years

Percutaneous balloon mitral commissurotomy (PBMC) is now first-line therapy in patients with symptomatic mitral stenosis (MS) and favorable valve morphology. Unfortunately, the outcome of Medicare-aged patients undergoing this procedure has not previously been defined. The results of PBMC in 55 patients > or = 65 years old (71 +/- 6 years) with moderate or severe MS were compared with 268 younger patients (47 +/- 10). Preprocedural New York Heart Association functional class and pulmonary pressures did not differ. The older patients had higher blood pressure, were more likely to be in atrial fibrillation and had higher valve scores (9.9 +/- 2.5 vs 8.6 +/- 2.2, p = 0.001). Procedural success was higher in the younger group (71% vs 55%, p = 0.013), with a greater increase in mitral valve area. Complications were similar in both groups and there were no periprocedural deaths. At 6 months a significant improvement in function class was seen in both groups. Restenosis, as assessed by serial echocardiography, occurred at a rate of 0.06 cm(2)/year in both groups, and functional class remained unchanged over 3 years. Event-free survival was similar at 48 months: 76% in the younger group and 69% in the older group. Our data thus demonstrates that PBMC can be safely performed in the Medicare-aged population. Despite less acute success in the older population, complication rates do not differ and decrement in valve area over time occurs at a similar rate. Functional class remains improved and event-free survival over 4 years appears similar in both groups. PBMC should thus be offered to patients with MS and suitable anatomy regardless of their age.

Instability of shoulder arthroplasty: balancing mobility and stability

Avoidance of instability after shoulder arthroplasty is based on an appreciation of normal articular anatomy and its restoration, as well as adequate soft tissue release and secure repair of subscapularis. Errors in restoration of articular anatomy, or disruption of soft tissues about the joint, are the principal reasons for instability. Revision in such cases can be challenging because of difficulties in restoring normal articular position and orientation, as well as reconstruction of deficient soft tissues.

Superior labral lesions: anatomy, pathology, and treatment

In 1985, Andrews et al first described superior labral lesions primarily located in the anterosuperior aspect of the labrum in 73 athletes who throw overhead. Subsequently, Snyder et al coined the term superior labrum anterior to posterior lesion by identifying and classifying injury to the labrum that originated posteriorly and extended anteriorly. During the past 15 years, these superior labral injuries have been the source of approximately 70 peer-reviewed publications in the English language literature. Substantial debate continues, however, with reference to the pathogenesis, diagnosis, and treatment of these lesions. The current review defines the anatomy, possible etiologies, diagnosis, and treatment of injuries to the superior labrum.

Shoulder proprioception in baseball pitchers

We examined proprioceptive differences between the dominant and nondominant shoulders of 21 collegiate baseball pitchers without a history of shoulder instability or surgery. A proprioceptive testing device was used to measure kinesthesia and joint position sense. Joint position sense was significantly (P =.05) more accurate in the nondominant shoulder than in the dominant shoulder when starting at 75% of maximal external rotation and moving into internal rotation. There were no significant differences for proprioception in the other measured positions or with kinesthesia testing. Six pitchers with recent shoulder pain had a significant (P =.04) kinesthetic deficit in the symptomatic dominant shoulder compared with the asymptomatic shoulder, as measured in neutral rotation moving into internal rotation. The net effect of training, exercise-induced laxity, and increased external rotation in baseball pitchers does not affect proprioception, although shoulder pain, possibly due to rotator cuff inflammation or tendinitis, is associated with reduced kinesthetic sensation.

Arthroscopic shoulder reconstruction: fast-track recovery and outpatient treatment

Arthroscopic shoulder reconstructive surgery has been handled in many different ways. However, there currently is significant evidence and experience to show that doing this surgery on an outpatient basis is not only cost-effective and efficient, but safe and beneficial to patients. New arthroscopic surgical techniques and the use of regional interscalene anesthesia have been shown to provide effective and comfortable intraoperative conditions, while allowing for prolonged analgesia and quicker recovery with minimal side effects. The authors will discuss their approach to surgery, anesthesia, and recovery for outpatient shoulder reconstruction.

Arthroscopic Bankart repair with the Suretac device for traumatic anterior shoulder instability in athletes

Arthroscopic treatment of anterior shoulder instability in the athlete has evolved tremendously over the past decade. Currently, most techniques include the use of suture and suture anchors. However, the variety of arthroscopic instruments and techniques that are available shows the complexity of intra-articular tissue fixation, which includes anchor placement, suture passing, and knot tying. Stabilization using the Suretac device (Acufex Microsurgical, Mansfield, MA) simplifies tissue fixation by eliminating the need for arthroscopic suture passing and intra-articular knot tying. However, a successful outcome is highly dependent on accurate patient selection. Preoperative evaluation, examination under anesthesia, and the pathoanatomy defined by a thorough arthroscopic examination suggest the most effective treatment strategy. The ideal candidate for shoulder stabilization using the Suretac device is an athlete with a relatively pure traumatic anterior instability pattern with detachment pathology (e.g., Bankart lesion) and minimal capsular deformation.

Management of massive irreparable rotator cuff tears: the role of tendon transfer

The inability to repair a rotator cuff tear is not uncommon, and in practices devoted to the management of shoulder injuries up to 30% of rotator cuff tears may be irreparable. The anterior and posterior components of the rotator cuff are the most important deficient areas. In the case of an irreparable subscapularis tendon tear, pain relief and stability appear to be reliably achieved by a split pectoralis major transfer; however, functional improvement is less certain because the biomechanics associated with this tendon transfer do not appear to be optimal. In the case of an irreparable posterosuperior rotator cuff tear, a latissimus dorsi tendon transfer reliably restores flexion and relieves pain; however, its use after failure of prior rotator cuff surgery makes the outcome less predictable. Both anterior and posterior reconstructions with tendon transfer require precise surgical technique and patient compliance with postoperative rehabilitation.

Diagnosis and treatment of anterosuperior rotator cuff tears

Nineteen of 407 patients who underwent rotator cuff repair surgery over a 6-year period were found to have a tear of the subscapularis in combination with the supraspinatus and infraspinatus tendons. Nine of these patients had an unsuccessful prior surgery, which failed to recognize the extent of the subscapularis component. Surgical repair of the subscapularis tendon required a deltopectoral approach, and repair of the supraspinatus and infraspinatus components of the tear could only be accomplished through this approach in 4 patients. In the remaining 15, an extended superior approach was required to mobilize and repair the supraspinatus and infraspinatus tendons. In all cases, the biceps tendon was either torn or severely degenerated, requiring tenodesis. At a mean follow-up of 40 months (range 24 to 75 months), subjective results were excellent in 5 patients, good in 3, fair in 4, and poor in 7. The modified Constant score improved to a mean of 69% (range 23% to 130%), compared with a preoperative mean of 38% (range 23% to 100%). Physical findings positive for subscapularis insufficiency persisted in 14 of 19 patients. A significant correlation (P <.05) was found between a lower Constant score and duration of symptoms longer than 6 months as well as an appearance of severe fatty degeneration and atrophy of the subscapularis muscle on magnetic resonance imaging. We conclude that anterosuperior rotator cuff tears are an infrequent configuration that may require surgical repair through an extended approach combining deltopectoral mobilization of the subscapularis with transdeltoid mobilization of the supraspinatus and infraspinatus. Repair before 6 months of symptoms is associated with a better functional outcome and is the result of less involution of muscle and tendon tissue.

Inhaled nitric oxide selectively dilates pulmonary vasculature in adult patients with pulmonary hypertension, irrespective of etiology

OBJECTIVES

We sought to compare the responses of patients with pulmonary hypertension from primary and secondary causes (PPH and SPH, respectively) to inhaled nitric oxide (iNO) in the cardiac catheterization laboratory.

BACKGROUND

Pulmonary hypertension can lead to right ventricular pressure overload and failure. Although vasodilators are effective as therapy in patients with PPH, less is known about their role in adults with SPH. Inhaled nitric oxide can accurately predict the response to other vasodilators in PPH and could be similarly utilized in SPH.

METHODS

Forty-two patients (26 to 77 years old) with pulmonary hypertension during cardiac catheterization received iNO. Demographic and hemodynamic data were collected. Their response to iNO was defined by a decrease of > or =20% in mean pulmonary artery (PA) pressure or pulmonary vascular resistance (PVR).

RESULTS

Mean PA pressures and PVR were lower during nitric oxide (NO) inhalation in all patients with pulmonary hypertension. Seventy-eight percent of patients with PPH and 83% of patients with SPH were responders to iNO. A trend was seen toward a greater response with larger doses of NO in patients with SPH. Nitric oxide was a more sensitive predictor of response (79%), compared with inhaled oxygen (64%), and was well tolerated, with no evidence of systemic effects. Elevation in right ventricular end-diastolic pressure appeared to predict poor vasodilatory response to iNO.

CONCLUSIONS

Nitric oxide is a safe and effective screening agent for pulmonary vasoreactivity. Regardless of etiology of pulmonary hypertension, pulmonary vasoreactivity is frequently demonstrated with the use of NO. Right ventricular diastolic dysfunction may predict a poor vasodilator response.

Experimental investigation of reaction forces at the glenohumeral joint during active abduction

Reaction forces at the glenohumeral joint counterbalance the mass moment of the upper extremity during shoulder motion and are directly related to the activity of muscles across the joint. Because stability of the glenohumeral joint depends on compression of the humeral head into the glenoid, reaction forces constitute an important aspect of shoulder biomechanics. The objective of this study was to measure reaction forces at the glenohumeral joint during active scapula plane abduction. Furthermore, to clarify the relationship between the deltoid and supraspinatus muscles throughout abduction, this study investigated the effect of 4 variations of applied muscle forces on the magnitude and direction of glenohumeral reaction forces. We used a dynamic shoulder testing apparatus equipped with a force-moment sensor to directly measure reaction forces. Joint reaction forces increased throughout abduction and peaked at approximately 90 degrees for all testing conditions. The largest reaction forces occurred when the ratio of applied forces favored the supraspinatus tendon, whereas simulated paralysis of the supraspinatus resulted in a significant decrease in joint compression. There were no differences in direction of the reaction force between testing conditions. The results of this study indicate that the magnitude of glenohumeral joint reaction forces varies according to the ratio of forces between the supraspinatus and deltoid muscles. Thus, conditions characterized by either deltoid or supraspinatus dysfunction may result in abnormal loading mechanics at the glenohumeral joint. Understanding the relationship between rotator cuff function and glenohumeral reaction forces will aid in clarifying the importance of muscular activity to shoulder stability and strength as it relates to compression of the humeral head.

Comparison of arthroscopic and open anterior shoulder stabilization. A two to six-year follow-up study

BACKGROUND

Sixty-three consecutive patients with recurrent traumatic anterior shoulder instability underwent operative repair. The decision to select either arthroscopic Bankart repair or open capsular shift was based on the findings of an examination under anesthesia and the findings at the time of arthroscopy. Thirty-nine patients with only anterior translation on examination under anesthesia and a discrete Bankart lesion underwent arthroscopic Bankart repair with use of absorbable transfixing implants. Twenty-four patients with inferior translation in addition to anterior translation on examination under anesthesia and capsular laxity or injury on arthroscopy underwent an open capsular shift.

METHODS

Treatment outcomes for each group were determined according to the scoring systems of Rowe et al., the American Shoulder and Elbow Surgeons, and the Short Form-36. Failure was defined as recurrence of dislocation or subluxation or the finding of apprehension. Fifty-nine (94 percent) of the sixty-three patients were examined and filled out a questionnaire at a mean of fifty-four months (range, twenty-seven to seventy-two months) following surgery.

RESULTS

There were no significant differences between the two groups with regard to the prevalence of failure or any of the other measured parameters of outcome. An unsatisfactory outcome occurred after nine (24 percent) of thirty-seven arthroscopic repairs and after four (18 percent) of twenty-two open reconstructions. All cases of recurrent instability resulted from a reinjury in a contact sport or a fall less than two years postoperatively. The treatment groups did not differ with regard to patient age, hand dominance, mechanism of initial injury, duration of follow-up, or delay until surgery. Measured losses of motion were minimal and, with the exception of forward elevation, slightly more of which was lost after the open capsular shifts (p = 0.05), did not differ between the two forms of treatment. Approximately 75 percent of the patients in each group returned to their favorite recreational sports with no or mild limitations. As rated by the patients, the result was good or excellent after thirty-one (84 percent) of the arthroscopic procedures and after twenty (91 percent) of the open procedures.

CONCLUSIONS

Arthroscopic and open repair techniques for the treatment of recurrent traumatic shoulder instability yield comparable results if the procedure is selected on the basis of the pathological findings at the time of surgery.

Percutaneous stenting of right pulmonary artery stenosis in fibrosing mediastinitis

Pulmonary artery stenosis is an uncommon complication of fibrosing mediastinitis. Previous medical and surgical therapies have provided limited clinical efficacy without objective evidence of clinical improvement. With the advantages of limited invasiveness and absent need for prolonged drug therapy, percutaneous stent deployment to relieve pulmonary artery obstruction represents a novel treatment for this rare disorder.

Outcomes following interventions in small coronary arteries with the use of hand-crimped Palmaz-Schatz stents

Although coronary stenting has been shown to be effective, retrospective studies have suggested that stents do not provide better results than angioplasty in small coronary arteries. We sought to examine procedural, in-hospital, and long-term outcomes of patients undergoing small-vessel stenting with Palmaz-Schatz stents hand-crimped on a balloon catheter <3 mm in diameter. We retrospectively analyzed the outcomes of 117 patients who underwent this type of coronary stent implantation at Duke University Medical Center between January 1, 1997 and May 30, 1998. The clinical indications for percutaneous revascularization included unstable angina in 67.5% of patients, acute myocardial infarction in 4.3%, postinfarct angina in 3.4%, silent ischemia in 3.4%, and stable angina in 1% of patients. Quantitative angiographic analysis was performed immediately before angioplasty and after stent implantation. Stents were used for elective indications in 24%, for suboptimal angiographic result in 61.5%, and for abrupt and/or threatened closure in 14.5% of patients. Reference vessel diameter was similar before and after the procedure. Minimum luminal diameter increased from 0.63 to 2.35 mm, an acute gain of 1.72+/-0.43 mm. Percent stenosis decreased from 74.2% to 4.7%. The clinical composite of death (n = 1, 1%), nonfatal myocardial infarction (n = 6, 5.1%), and revascularization (n = 1, 1%) occurred in-hospital in only 8 patients (6.8%), resulting in clinical procedure success in 109 patients (93%). Our data suggest that stents designed for vessels >3.0 mm can be deployed in small vessels, with a low in-hospital event rate. However, target lesion revascularization in small vessels remains high. Development of antiproliferative strategies could improve long-term outcomes for small-vessel interventions.

Arthroscopic versus open Bankart repair for traumatic anterior shoulder instability

After more than 15 years of experience, arthroscopic shoulder stabilization is becoming less controversial. Historically, recurrence rates following arthroscopic stabilization have been higher than with open stabilization. Although a negligible advantage may exist in terms of expedited postoperative rehabilitation and improved postoperative recovery of motion, critics suggest that its use in contact athletes be limited. The indications for arthroscopic stabilization are expanding, in part, because of improved understanding of the pathophysiology of shoulder instability. Understanding the mechanism of recurrent instability following arthroscopic stabilization offers clues to how physicians can prevent unsatisfactory results in the future. With newer instrumentation and the ability to thermally treat capsular tissue, coexisting pathology, such as capsular plastic deformation, rotator interval lesions, and unrecognized intra-articular pathology, can now be addressed arthroscopically. The judicious use of these techniques is warranted until long-term study results become available. Ideal patients for arthroscopic Bankart repair have a discrete Bankart lesion; a robust, well-developed IGHL; no significant capsular laxity or intraligamentous injury; and an absence of concomitant intra-articular pathology. Additional findings on MR imaging or CT evidence of a discrete labral lesion and pure unidirectional anterior instability during EUA are also good prognostic indicators for arthroscopic Bankart repair. Arthroscopic criteria that render patients less appropriate for an arthroscopic repair include capsular injury, capsular laxity, a bony Bankart lesion, glenohumeral arthritis, and a rotator cuff tear. The authors' believe that either absent or patulous, poorly developed glenohumeral ligaments represent a poor prognostic indicator for a successful outcome following standard arthroscopic Bankart repair. Individuals with poor-quality tissue are more predictably managed using open capsulorrhaphy. Patients with pathologic ligamentous laxity in the absence of a Bankart lesion or any apparent intraligamentous injury to the IGHL are also good candidates for treatment with an open capsulorrhaphy. Findings determined from a thorough physical examination, EUA, and the pathology appreciated during diagnostic arthroscopy help to appropriately choose the surgical procedure that effectively addresses pathology in patients who present with recurrent traumatic anterior instability. Patient preferences and surgical experience are important determinants of procedure selection, and current arthroscopic techniques lack the versatility to uniformly address the entire spectrum of pathology that may be associated with traumatic anterior shoulder instability. Surgeons should always be prepared to convert to an open-stabilization technique if the arthroscopic technique is deficient in addressing all pathology identified at the time of surgery.

Arthroscopic Bankart repair. Operative technique and surgical pitfalls

The arthroscopic management of patients with shoulder instability continues to evolve. The obvious benefits include a reduction of operative time, preservation of the subscapularis, improved visualization, and less blood loss. Newer techniques that allow the plastic deformation of the IGHLC to be addressed are emerging, which may yield results as successful as those of open Bankart repair. The ability to adequately tension the IGHLC may result in some loss of external rotation, which may improve results. Capsular tensioning must be critically analyzed at the time of surgery. Adequate stabilization with an arthroscopic approach should provide a convincing postoperative examination of stability. A careful examination after suture placement may indicate residual laxity that must be addressed. Finally, periods of immobilization are similar in open and arthroscopic techniques. The process of biologic healing is not accelerated by arthroscopic techniques, and early return to sport activities that may endanger the repair will likely result in early failure.

Recognition and treatment of refractory posterior capsular contracture of the shoulder

SUMMARY

Limitation of internal rotation has been reported in conjunction with impingement syndrome of the shoulder. A group of 9 patients was identified who had discrete, painful loss of internal rotation associated with refractory impingement syndrome. The duration of symptoms averaged 18 months (range, 11 to 33 months), and all patients failed a course of physical therapy specifically addressing loss of internal rotation. Six patients reported traction as the mechanism of injury, and 3 developed motion loss and pain following a posterior capsular shift procedure. All patients underwent arthroscopy, and were observed to have a thickened posterior capsule. An arthroscopic release of the posterior capsule improved motion in all patients, with substantial relief of pain. At an average of 19 months follow-up (range, 11 to 35 months), internal rotation in 90 degrees of abduction improved from 10 degrees preoperatively to 47 degrees postoperatively, and there were no complications related to the procedure. We conclude that chronic loss of internal rotation secondary to posterior capsular contracture may be an explanation for refractory pain in some patients with an initial diagnosis of impingement syndrome. This condition appears to be amenable to arthroscopic posterior capsular release.

Selective capsular shift technique for anterior and anterior-inferior glenohumeral instability

Anterior and anterior-inferior glenohumeral instability is often successfully treated with nonoperative measures, especially in atraumatic instability. In the case of traumatic instability, especially when the labrum is detached from the anteroinferior glenoid rim, surgery is often necessary to stabilize the shoulder and restore function. An anatomic repair that addresses any capsular or labral defect is essential for a successful outcome, and the selective capsular shift technique offers the flexibility necessary to correct these deformities. Several equally important steps must be followed when treating anterior and anterior-inferior glenohumeral instability. These include the correct diagnosis and indications for surgery; a technically successful surgical procedure; and diligent, physician-directed, closely monitored rehabilitation.

In situ force distribution in the glenohumeral joint capsule during anterior-posterior loading

Our objective was to examine the function of the glenohumeral capsule and ligaments during application of an anterior-posterior load by directly measuring the in situ force distribution in these structures as well as the compliance of the joint. We hypothesized that interaction between different regions of the capsule due to its continuous nature results in a complex force distribution throughout the glenohumeral joint capsule. A robotic/universal force-moment sensor testing system was utilized to determine the force distribution in the glenohumeral capsule and ligaments of intact shoulder specimens and the joint kinematics resulting from the application of external loads at four abduction angles. Our results suggest that the glenohumeral capsule carries no force when the humeral head is centered in the glenoid with the humerus in anatomic rotation. However, once an anterior-posterior load is applied to the joint, the glenohumeral ligaments carry force (during anterior loading, the superior glenohumeral-coracohumeral ligaments carried 26+/-16 N at 0 degrees and the anterior band of the inferior glenohumeral ligament carried 30+/-21 N at 90 degrees). Therefore, the patient's ability to use the arm with the humerus in anatomic rotation should not be limited following repair procedures for shoulder instability because the repaired capsuloligamentous structures should not carry force during this motion. Separation of the capsule into its components revealed that forces are being transmitted between each region and that the glenohumeral ligaments do not act as traditional ligaments that carry a pure tensile force along their length. The interrelationship of the glenohumeral ligaments forms the biomechanical basis for the capsular shift procedure. The compliance of the joint under our loading conditions indicates that the passive properties of the capsule provide little resistance to motion of the humerus during 10 mm of anterior or posterior translation with anatomic humeral rotation. Finally, this knowledge also enhances the understanding of arm positioning relative to the portion of the glenohumeral capsule that limits translation during examination under anesthesia.

Contribution of the passive properties of the rotator cuff to glenohumeral stability during anterior-posterior loading

The passive properties of the rotator cuff have been shown to provide some stability during anterior-posterior (AP) translation. However, the relative importance of the rotator cuff to joint stability remains unclear. The purpose of this study was to quantify the force contributions of the rotator cuff and of capsuloligamentous structures at the glenohumeral joint during AP loading. We hypothesized that the rotator cuff acts as a significant passive stabilizer of the glenohumeral joint and that its contribution to joint stability is comparable to the contribution made by the components of the glenohumeral capsule. A robotic/universal force-moment sensor testing system was used to determine both the multiple "degrees of freedom" joint motion and the in situ force carried by each soft tissue structure during application of an 89N AP load at 4 abduction angles. The percent contribution of the rotator cuff to the resisting force of the intact joint during AP loading was significantly greater during posterior loading (35% +/- 26%) than during anterior loading at 60 degrees of abduction (P < .05). The contribution of the rotator cuff (i.e., 29% +/- 16% at 30 degrees of abduction) was found to be significantly greater than the contributions of the capsule components during posterior loading at 30 degrees, 60 degrees, and 90 degrees of abduction (P < .05). However, no differences could be found between the respective contributions of the rotator cuff and the capsule components during anterior loading. The results support our hypothesis and suggest that passive tension in the rotator cuff plays a more significant role than other soft tissue structures in resisting posterior loads at the glenohumeral joint. The important role of the rotator cuff during posterior loading may be a result of the thin posterior joint capsule compared with the anterior capsule, which has several thickenings. This information increases our understanding of posterior stability at the glenohumeral joint during clinical laxity tests.

An analytical approach to determine the in situ forces in the glenohumeral ligaments

The purpose of this study was to use an analytical approach to determine the forces in the glenohumeral ligaments during joint motion. Predictions from the analytical approach were validated by comparing them to experimental data. Using a geometric model, the lengths of the four glenohumeral ligaments were determined during anterior-posterior loading simulations and forward flexion-extension. The corresponding force in each structure was subsequently calculated based on length data via load-elongation curves obtained experimentally. During the anterior loading simulation at 0 deg of abduction, the superior glenohumeral ligament carried up to 71 N at the maximally translated position. At 90 deg of abduction, the anterior band of the inferior glenohumeral ligament had the highest force of 45 N during anterior loading. These results correlated well with those found in previous experimental studies. We believe that this validated analytical approach can be used to predict the forces in the glenohumeral ligaments during more complex joint motion as well as assist surgeons during shoulder repair procedures.

Effect of joint compression on inferior stability of the glenohumeral joint

To determine the relative importance of negative intraarticular pressure, capsular tension, and joint compression on inferior stability of the glenohumeral joint we studied 17 fresh, normal adult cadaver shoulders using a "3 degrees of freedom" shoulder test apparatus. Translations were measured in intact and vented shoulders while a 50-N superior and inferior directed force was applied to the shoulder. Three different joint compressive loads (22 N, 111 N, 222 N) were applied externally. Tests were performed in 3 positions of humeral abduction in the scapular plane (0 degree, 45 degrees, 90 degrees) and in 3 positions of rotation (neutral, maximal internal, and maximal external). After tests of the intact and vented shoulder, the glenohumeral ligaments were sectioned and tests were repeated. With minimal joint compression of 22 N, negative intraarticular pressure and capsular tension limited translation of the humeral head on the glenoid. Increasing the joint compressive load to 111 N resulted in a reduction of mean inferior translation from 11.0 mm to 2.0 mm at 0 degree abduction, from 21.5 mm to 1.4 mm at 45 degrees abduction, and from 4.5 mm to 1.2 mm at 90 degrees abduction. With a compressive load of 111 N, venting the capsule or sectioning of glenohumeral ligaments had no effect on inferior stability.

CLINICAL RELEVANCE

Glenohumeral joint compression through muscle contraction provides stability against inferior translation of the humeral head, and this effect is more important than negative intraarticular pressure or ligament tension.

Glenoid fracture nonunion presenting as instability in a young athlete

A case of a teenage athlete with a 4-year history of shoulder pain caused by glenoid fracture nonunion is presented. This individual had findings consistent with traumatic anterior shoulder instability as well as normal radiographs. Arthroscopy showed a nondisplaced glenoid fracture that was stabilized successfully through a deltopectoral approach.

The treatment of symptomatic os acromiale

During a four-year period, fourteen individuals (fifteen shoulders) who had been seen at the shoulder service of our institution because of pain in the shoulder had a radiographic finding of an os acromiale. On clinical examination, the pain appeared to be due to an unstable os acromiale because the patients had point tenderness over the acromion and pain on forward elevation of the shoulder. The diagnosis of an os acromiale was confirmed on radiographs, magnetic resonance images, or a bone scan. Eight patients had an associated tear of the rotator cuff. The os acromiale was located in the pre-acromion in one shoulder, the meso-acromion in eleven shoulders, and the meta-acromion in three shoulders. At the operation, the anterior aspect of the acromion was found to be unstable in all shoulders. Eleven patients (twelve shoulders) had open reduction of the os acromiale and insertion of an autogenous iliac-crest bone graft. Of those patients, four (five shoulders) had open reduction and internal fixation with a tension-band procedure with use of pins and wires. Only one of those shoulders had a solid osseous union, and the other four shoulders had a non-union that was due to a disruption of the fixation. The remaining seven patients (seven shoulders) had open reduction and internal fixation with use of cannulated screws and a tension-band construct; a solid osseous union was achieved in all but one of them. One patient had excision of the pre-acromion, which relieved the pain. Two patients who had had failed open reduction and internal fixation had excision of a grossly unstable os acromiale in the meso-acromion; both patients had pain and weakness after this procedure. Of the twelve shoulders that had open reduction and bone-grafting, seven had union of the os acromiale; the average time to radiographic and clinical union was nine weeks (range, seven to twenty weeks). We concluded that, although it is rare, symptomatic unstable os acromiale does occur and can be effectively treated with use of autogenous bone-grafting and internal fixation with a rigid tension-band construct and cannulated screws.

Articular contact patterns of the normal glenohumeral joint

The purpose of this study was to determine the articular contact patterns of the normal glenohumeral joint, and to correlate these findings with cartilage and subchondral bone architecture. We studied 10 normal shoulders of cadavers. We removed all soft tissues except the joint capsule and rotator cuff and then placed the shoulders on a testing apparatus that allowed freedom of translation in three planes. After the humerus was placed in a neutral position of rotation, articular contact patterns were measured with specially prepared prescale Fuji film so that it could be inserted between the joint surfaces. Articular contact was analyzed with 222 and 444 N of joint compressive load, and the humerus was positioned in scapular plane abduction of 0 degree, 45 degrees, and 90 degrees. The contact patterns were then digitized to determine percentage contact of the humeral head on the glenoid. We studied 12 additional cadaver shoulders with fine microradiographs and histologic techniques after we sectioned the glenoids in the anterior-posterior and superior-inferior planes. We then analyzed articular and subchondral architecture. We found that when the shoulder was adducted the contact area of the humeral head on the glenoid was limited to the anatomic region of the central glenoid known as the "bare area." This was histologically and radiographically an area of cartilage thinning and increased subchondral bone density. As the shoulder was abducted the articular congruity and percentage contact area increased. We concluded that there was a slight articular mismatch with the shoulder adducted in the normal shoulder. Histologic and radiographic studies suggested that the central bare area region of the glenoid was a region of increased compressive loading. As the shoulder was abducted the joint became more congruent and thus the contact area of the humeral head on the glenoid increased.

Serratus anterior dysfunction. Recognition and treatment

Recognition of scapular winging may be difficult, and potential errors in treatment can result. Such treatment errors may cause morbidity for the patient. In addition, electrical evidence of long thoracic nerve injury usually is required to confirm the etiology of scapular winging as being caused by serratus anterior dysfunction. Although various conditions may result in scapular winging, primary serratus anterior dysfunction can be treated effectively by transfer of the pectoralis major tendon; however, this surgical approach sometimes may given an unacceptable cosmesis, and there may be local morbidity to the donor site of the iliotibial band graft that is used to augment the tendon transfer. The authors report eight patients with primary chronic scapulothoracic winging refractory to conservative treatment. Five of these patients had an incorrect diagnosis, and this resulted in 17 surgical procedures without resolution of their pain or improvement of function. Of the eight patients who required additional surgery to stabilize the scapula, only five patients had an electromyographic study that showed long thoracic nerve palsy, although all patients had profound scapulothoracic winging. All patients underwent a modified pectoralis major transfer with autogenous semitendinosus and gracilis tendon augmentation using two small incisions. Although one patient had a postoperative infection develop, the remaining seven patients had resolution of their winging, improved function, and satisfactory cosmesis.

A dynamic analysis of glenohumeral motion after simulated capsulolabral injury. A cadaver model

We used a dynamic shoulder-testing apparatus and nine fresh-frozen, entire upper extremities from cadavera to evaluate the effects of varying degrees of capsulolabral injury on the kinematics of the glenohumeral joint during abduction in the scapular plane and external rotation. Joint kinematics were recorded with use of a six-degrees-of-freedom magnetic tracking device before and after the creation of each capsulolabral lesion in a progressive manner. Dislocation did not occur after simulation of a large Bankart lesion or even after sectioning of the anterior aspect of the joint capsule. However, division of the entire joint capsule (that is, both the anterior aspect and the posterior aspect) resulted in a significant increase (p < 0.05) in posterior translation during abduction in the scapular plane, and two of the nine shoulders dislocated posteriorly. External rotation of the abducted extremity produced no increase in anterior or posterior translation.

Combined Bankart and HAGL lesion associated with anterior shoulder instability

Traumatic anterior shoulder instability has been shown to be associated with a spectrum of capsulolabral pathology, including separation of the labrum (Bankart lesion), capsular rupture, and humeral avulsion of the glenohumeral ligaments (HAGL lesion). We describe a case of combined Bankart and HAGL lesions, a condition that has not been described before. Careful anatomic repair of both components of this bipolar capsular injury resulted in an excellent outcome.

Shoulder kinematics with two-plane x-ray evaluation in patients with anterior instability or rotator cuff tearing

The goals of this study were to define biplanar glenohumeral kinematics and glenohumeral-scapulothoracic motion relationships in normal patients with a two-plane radiograph series and then in patients with anterior shoulder instability or rotator cuff tear both before surgery and after surgical repair and postoperative rehabilitation. A two-plane radiographic series of x-ray films in the scapular and horizontal (axillary) planes was performed. With these films, measurements of the relationship between the centers of the humeral head and glenoid and measurements of the component contributions of glenohumeral and scapulothoracic motion to total arm abduction were made. Six normal adults underwent x-ray evaluation to establish normal control values. Kappa analysis was used to determine reliability of technique. Eighteen patients with confirmed anterior shoulder instability (group A) and 15 with confirmed rotator cuff tears (group B) were studied before surgery. Seven (39%) of 18 of the patients in group A and all 15 (100%) of the patients in group B demonstrated superior translation of the humeral head during scapular plane abduction. In the horizontal plane 14 (78%) of 18 patients in group A (instability) and none in group B (rotator cuff tear) demonstrated abnormal anterior translation of the humeral head on the glenoid. Both groups demonstrated altered glenohumeral-scapulothoracic motion relationships compared with the normal control group. Two years after surgery 12 patients from group A and 14 patients from group B were restudied. All of these patients had demonstrated abnormalities of humeral head translation before surgery. For group A 12 (100%) of 12 patients demonstrated normal glenohumeral kinematics in both planes after open anterior stabilization. For group B 12 (86%) of 14 patients demonstrated normal glenohumeral kinematics in both planes after open rotator cuff repair. In group A the altered glenohumeral-scapulothoracic motion relationships persisted, whereas in group B these relationships became normal.

Surgical treatment of postoperative deltoid origin disruption

Although it is well recognized that deltoid disruption after shoulder surgery is associated with poor function, little information is available regarding results of surgical treatment for this problem. Twenty-four patients underwent direct repair or rotational deltoidplasty reconstruction of a detached muscle origin after shoulder surgery. The original surgical procedure was rotator cuff repair in 12, acromioplasty in four, and lateral acromionectomy with or without rotator cuff repair in eight. The average duration of symptoms before deltoid reconstruction was 17 months. The mean followup was 39 months (range, 13-84 months). Twelve patients reported moderate to severe pain, whereas 12 had minimal pain. Two patients required a shoulder fusion for intractable pain. Overall, one (4%) excellent, seven (29%) good, and 16 (67%) unsatisfactory results were observed. A poor outcome was associated with a prior lateral acromionectomy, involvement of the middle deltoid, a massive rotator cuff tear with weakness in external rotation, and a residual postoperative defect larger than 2 cm. In select cases, repair or deltoidplasty can improve function and pain.

Arthroscopic-assisted rotator cuff repair: patient selection and treatment outcome

Over a 4-year period 24 patients out of 376 who required a rotator cuff repair were selected for arthroscopic-assisted rotator cuff repair. Preoperative selection criteria were refractory pain in the setting of good range of motion and strength (after an impingement test), absence of radiographic superior humeral head translation, and magnetic resonance imaging evidence of minimally retracted tear without rotator cuff muscle atrophy. Intraoperative selection criteria were the findings of an avulsion-type tear configuration with good tendon quality and absence of subscapularis tendon involvement. Based on these intraoperative criteria, 7 of the 24 patients were converted to an open approach to mobilize retracted and friable tendon tissue in a complex tear configuration. The remaining 17 patients underwent a transosseous arthroscopic-assisted rotator cuff repair with an average postoperative follow-up of 23 months. Evaluation by an independent therapist determined the postoperative American Shoulder and Elbow Surgeons Shoulder Function Index of 96 +/- 3 for the operative shoulder. The Functional Rating Scores for Activities of Daily Living and Sports Activity Score were 89% +/- 10% and 87% +/- 12%, respectively. Instrumented isometric strength for abduction and external rotation strength in the operated shoulder were 94% +/- 20% and 93% +/- 20%, respectively, compared with the contralateral unoperated side. Five of eight patients who performed overhead sports returned to a premorbid level of performance, and 14 of 15 patients available for follow-up believed that their result was excellent. We conclude that through careful selection one can identify patients optimally suited for arthroscopic-assisted rotator cuff repair, but some may have to be converted to an open end approach because of the quality of the tendon tissue and configuration of the tear requiring soft tissue releases.

Arthroscopic release of postoperative capsular contracture of the shoulder

A loss of motion after an operation on the shoulder often cannot be treated successfully with physical therapy or closed manipulation. Although open release techniques generally improve motion, they involve extensive dissection. We developed a technique of arthroscopic capsular release and applied it in eighteen patients who had postoperative stiffness of the shoulder. The patients were selected for the arthroscopic release technique if a conservative program of physical therapy and an attempted closed manipulation had failed to restore motion and if they had no known extra-articular contractures. Five of the thirteen patients who had had a global loss of shoulder motion had motion restored with the anterior capsular release, and six needed an additional release of the posterior aspect of the capsule--that is, a combined (anterior and posterior) capsular release. The arthroscopic procedure could not be completed in the remaining two patients because of an extra-articular scar involving the subscapularis, but those patients were managed successfully with an open release. As five patients had lost only internal rotation and flexion, they had only a posterior capsular release. For the eleven patients who had had either an anterior or a combined (anterior and posterior) capsular release, the mean improvement in the score of Constant and Murley was 43 points (range, 31 to 62 points) and all improvements in motion were significant (p < 0.01). Flexion improved a mean of 51 degrees (range, 10 to 65 degrees); external rotation in adduction and abduction, 31 degrees (range, 10 to 50 degrees) and 40 degrees (range, 5 to 80 degrees), respectively; and internal rotation in adduction and abduction, six spinous-process levels (range, three to eleven levels) and 41 degrees (range, 20 to 70 degrees), respectively. For the five patients who had an isolated posterior capsular release, the score of Constant and Murley improved a mean of 20 points (range, 5 to 35 points) and the improvements in motion also were significant (p < 0.05 and 0.005). Internal rotation in adduction and abduction improved a mean of four spinous-process levels (range, one to ten levels) and 42 degrees (range, 30 to 60 degrees), respectively. Eight patients had an arthroscopic acromioplasty for concomitant impingement disease. One patient who had had a combined (anterior and posterior) release and one who had had a posterior capsular release continued to have pain because of injury of the articular cartilage from a previous operation. We concluded that arthroscopic capsular release is a reliable method for restoring motion with minimum morbidity in carefully selected patients who have postoperative stiffness of the shoulder. When necessary, it can be converted to an open release.

Optic nerve contact and compression by the carotid artery in asymptomatic patients

PURPOSE

To estimate the frequency and clinical correlates of contact and compression of the intracranial optic nerve by the supraclinoid carotid artery in asymptomatic patients.

METHODS

In a retrospective study, we identified asymptomatic patients who had undergone magnetic resonance imaging with sequences that could be used to evaluate the relation between the intracranial optic nerve and the carotid artery. These patients underwent neuroimaging evaluations for reasons unrelated to loss of vision, optic neuropathy, or carotid artery disorders. The relation between the optic nerve and carotid artery was graded in a standardized manner. The effect of a number of clinical covariates on the risk of compression was evaluated using multiple logistic regression.

RESULTS

The frequencies of some of the artery-nerve relationships included contact of one or both optic nerves in 70 (70%) of 100 patients; bilateral compression in 12 (12%) of 100 patients; and unilateral compression with no arterial contact or compression on the opposite side in five (5%) of 100 patients. The estimated odds of compression were significantly increased as the diameter of the carotid artery increased.

CONCLUSIONS

Among asymptomatic patients, supraclinoid carotid artery contact with the intracranial optic nerve occurs frequently. Anatomic compression, on the other hand, especially when unilateral, occurs infrequently. The risk of anatomic compression of the optic nerve is directly proportional to the diameter of the carotid artery.

The rotator cuff. Commentary

To add clinical perspective to the articles of this two-issue collection, eight prominent shoulder surgeons discuss their approach to the treatment of rotator cuff disease. There is broad agreement in many areas, however, significant controversies remain.

Rotator cuff disease. An arthroscopic view

Rotator cuff disease has become a treatable entity by using the arthroscope; however, a sound understanding of pathology and an appreciation of relevant physical findings are necessary if the arthroscope is to be used effectively. Arthroscopic examination confirms the extent of rotator cuff disease and co-morbid pathology and allows for treatment of many problems related to the rotator cuff.

Single-tendon tears of the rotator cuff. Evaluation and treatment of subscapularis tears and principles of treatment for supraspinatus tears

Successful surgical treatment of single-tendon tears, which involve the supraspinatus or the subscapularis requires careful attention to technical details. In supraspinatus tears, careful mobilization and secure repair of the tendon will usually give a good outcome. In subscapularis tears, the diagnosis is not difficult if one carefully evaluates the patient for the classic pathognomonic findings of such a tear. If the tear is confirmed by CT or MR imaging and an acute repair is performed, the outcome is usually satisfactory.

Arthroscopic release for chronic, refractory adhesive capsulitis of the shoulder

Idiopathic adhesive capsulitis usually responds to gentle physical therapy or, if that fails, to closed manipulation with the patient under anesthesia. In some patients, however, loss of motion may be refractory to either of these treatments and an operative release may be indicated. We are reporting on the technique and results of arthroscopic capsular release as a new alternative for the management of such patients. During a three-year period, we managed twenty-three patients who had idiopathic adhesive capsulitis that had failed to respond to physical therapy or closed manipulation. These patients had an arthroscopic anterior capsular release and received forty-eight hours of intensive physical therapy as inpatients. During the physical therapy, the patients received an interscalene regional analgesic with use of repeated nerve blocks or with a continuous infusion through an interscalene catheter. This was followed by a supervised outpatient physical-therapy program. Six patients also had an arthroscopic acromioplasty for the treatment of impingement. There were no complications related to any of the procedures. At a mean of thirty-nine months (range, twenty-four to sixty-four months) after the arthroscopic procedure, the improvement in the score of Constant and Murley averaged 48 points (range, 13 to 77 points). The mean improvement in motion was 49 degrees (range, 0 to 105 degrees) for flexion; 42 degrees (range, 10 to 80 degrees) and 53 degrees (range, 0 to 100 degrees) for external rotation in adduction and abduction, respectively; and eight spinous-process levels (range, three to fourteen levels) and 33 degrees (range, 30 to 60 degrees) for internal rotation in adduction and abduction, respectively. These gains in motion were all significant (p < 0.01) compared with the preoperative values and were within a mean of 7 degrees of the values for the contralateral, normal shoulder. We concluded that, in patients who have loss of motion that is refractory to closed manipulation, arthroscopic capsular release improves motion reliably with little operative morbidity.

Idiopathic hypertrophic cranial pachymeningitis: clinical-radiological-pathological correlation of bone involvement

We present the clinical, radiological, and pathological findings in an elderly man who developed a progressive superior orbital fissure syndrome due to idiopathic hypertrophic cranial pachymeningitis. The unique aspect of this case concerned the increased density of the sphenoid ridge and lateral orbital wall observed by using computed tomography, and the enhancement of the marrow signal seen on magnetic resonance imaging. These neuroimaging abnormalities of bone resulted from an indirect nonspecific response of the marrow to the adjacent soft tissue and dural inflammatory process.

An arthroscopic technique for anterior stabilization of the shoulder with a bioabsorbable tack

Arthroscopically assisted repair of the anterior aspect of the labrum with use of a bioabsorbable tack was performed in fifty-two consecutive patients who had chronic anterior instability of the shoulder. The average age of the patients was twenty-eight years (range, sixteen to fifty years). The etiology of the instability was a traumatic injury in forty-nine patients; twenty-six of those injuries were sustained during participation in a contact sport. Fifty shoulders had a Bankart lesion. The patients were evaluated at an average of forty-two months (range, twenty-four to sixty months) after the procedure. Forty-one (79 per cent) of the patients were asymptomatic and were able to participate in sports without restriction. The repair was considered to have failed in eleven (21 per cent) of the patients. In four of them, the failure resulted from a single traumatic reinjury during participation in a contact sport, and three of these reinjuries were treated nonoperatively. The remaining seven failures occurred atraumatically. Eight patients had an open glenoid-based capsulorrhaphy as a consequence of recurrent instability. At the reoperation, no evidence of the tack was found in any patient. In seven patients, the Bankart lesion had completely healed, and the anteroinferior aspect of the capsule was patulous. Anterior stabilization of the shoulder with a bioabsorbable tack may be indicated for patients who have anterior instability but do not need a capsulorrhaphy or capsular imbrication to reduce the joint volume.

Role of proprioception in pathoetiology of shoulder instability

Proprioception is a specialized sensory modality that gives information about extremity position and direction of movement. This kind of afferent sensory feedback is probably important in mediating muscular control of the shoulder joint. As this articulation is minimally constrained, such a coordinated dynamic control of muscles about the joint is necessary for stability during arm motion. The authors evaluated proprioception in individuals with normal shoulders, unstable shoulders, and after surgical stabilization, by assessing threshold to detection of passive motion and the ability to passively reposition the arm in space. In normal shoulders there is no difference between the dominant and nondominant shoulder, though in unstable shoulders there is a significantly decreased proprioceptive ability. Surgical stabilization normalizes proprioception of the shoulder.

Tensile properties of the superior glenohumeral and coracohumeral ligaments

Recent evidence has shown that the superior glenohumeral ligament (SGHL) and coracohumeral ligament (CHL) are important static stabilizers. To clarify the function of these two ligaments, we studied their tensile properties with bone-ligament-bone complexes from fresh-frozen shoulders, 10 SGHLs and 10 CHLs. Each ligament's cross-sectional area was measured, and uniaxial tensile testing of each complex was performed. The stiffness, ultimate load, percent elongation, and energy absorbed to failure of each bone-ligament-bone complex were derived from its load-elongation curve. The cross-sectional area of the coracohumeral ligament was significantly greater than that of the superior glenohumeral ligament of their midportions (CHL, 53.7 +/- 3.2 mm2 vs. SGHL, 11.3 +/- 1.6 mm2, p < 0.05). Results also reveal significant differences between the tensile properties for the two ligaments, with the coracohumeral ligament possessing greater stiffness (CHL, 36.7 +/- 5.9 N/mm vs. SGHL, 17.4 +/- 1.5 N/mm, p < 0.05) and ultimate load (CHL, 359.8 +/- 40.3 N vs. SGHL, 101.9 +/- 11.5 N, p < 0.05) than the superior glenohumeral ligament. Our findings confirm that the coracohumeral ligament is an important capsuloligamentous structure of the glenohumeral joint.