Arthroscopic rotator cuff repair: Analysis of results by tear size and by repair technique-margin convergence versus direct tendon-to-bone repair.

PURPOSE: The purpose of this article is 2-fold: To report the long-term functional results of arthroscopic rotator cuff repair (average, 3.5 years in this study), and to analyze results by tear size and repair technique (margin convergence v direct tendon-to-bone repair). TYPE OF STUDY: Case series. METHODS: Between September 1993 and April 1997, 62 patients had an arthroscopic rotator cuff repair performed by the senior author (S.S.B.). Of this group, 59 patients (59 shoulders) were available for follow-up. Preoperative and postoperative function were assessed by means of a modified UCLA scoring system. Tears were categorized according to size (greatest diameter, number of tendons involved, and pattern of tear [crescent shape v U-shape]). Crescent-shaped tears were repaired in a direct tendon-to-bone fashion and U-shaped tears were repaired by a margin-convergence technique. RESULTS: Good and excellent results were achieved in 95% of the cases, regardless of tear size. The large and massive tears did as well as the small and medium-sized tears. That is, results were independent of tear size (P >.05). Results of tears repaired by margin convergence were not significantly different statistically from those repaired by direct tendon-to-bone repair (P >.05), validating the selection criteria of U-shaped tears for repair by margin convergence. There is a rapid return to full overhead function after arthroscopic rotator cuff repair (average, 4 months for each tear size). Delay from injury to surgery, even of several years, did not adversely affect surgical outcome. CONCLUSIONS: (1) Arthroscopic rotator cuff repair can achieve good and excellent results in a large percentage of patients (95% in this series). (2) Results of arthroscopic rotator cuff repair are independent of tear size. (3) U-shaped tears repaired by margin convergence have results comparable to those of crescent-shaped tears repaired directly by a tendon-to-bone technique. (4) There is a rapid return to full overhead function after arthroscopic rotator cuff repair (average, 4 months for all tear sizes). (5) A delay from injury to diagnosis, even of several years, is not a contraindication to arthroscopic rotator cuff repair.

Arthroscopic treatment of massive rotator cuff tears.

In the past 10 years, arthroscopic surgeons have gone from being unable to repair any rotator cuff tears arthroscopically to being able to repair virtually all rotator cuff tears, even complex massive tears, arthroscopically. The factors responsible for this rapid evolution have been: (1) recognition of the mechanical principles responsible for a secure repair (margin convergence, knot security, loop security); (2) recognition of major tear patterns that require different techniques of repair; and (3) development of instrumentation and arthroscopic portals that predictably accomplish secure repair of the rotator cuff and direct access to the pathologic areas. In the current study, the author analyzes each factor, anatomic and mechanical, that influences the quality of the repair, and explains how to optimize the overall repair by optimizing each step in the repair. In the author's series of arthroscopic repair of rotator cuff tears, the results have been gratifying, with massive tears achieving final results equivalent to those of smaller tears.

Optimization of stacked half-hitch knots for arthroscopic surgery.

PURPOSE: This study was conducted to determine the optimal configuration of stacked half-hitch knots that would give the maximum knot-holding capacity (KHC). TYPE OF STUDY: Mechanical testing study. METHODS: The 2 types of suture materials tested were No. 1 PDS II monofilament and No. 2 Ethibond braided (Ethicon, Somerville, NJ) because these are the 2 most commonly used sutures in arthroscopic surgery. Twelve configurations of stacked half-hitch knots including 2 versions of the Revo knot were tested. Knots were tied between 2 steel hooks 7 mm apart on a manual knot-testing machine. The steel hooks were spread apart to break the knot and the KHC was determined by the peak load recorded on the digital force transducer. Maximum KHC was achieved for No. 1 PDS II sutures by locking the knot with 2 RHAPs (reversing half-hitch on alternate post) and, for No. 2 Ethibond sutures, by locking the knot with 3 RHAPs. Because of the possibility of PDS II sutures unraveling, it is recommended for both No. 1 PDS II and No. 2 Ethibond sutures, that all stacked half-hitches be locked with 3 RHAPs. By adding 1 RHAP to the Revo knot, failure by slippage can be eliminated. RESULTS: The recommended knots tied with braided No. 2 Ethibond sutures were 1.5 times stronger than knots tied with No. 1 PDS II sutures. Although there was variability in the KHC of the recommended knots tied by different surgeons using different knot tiers, the greatest difference in the mean KHC was less than 10%. CONCLUSIONS: Stacked half-hitch knots locked with 3 RHAPs are unlikely to fail by slippage.

Turbulence control as a factor in improving visualization during subacromial shoulder arthroscopy.

Bleeding in the subacromial space is an annoying but ever-present impediment to visualization during arthroscopic subacromial procedures. Direct (thermal electrocautery) and indirect (hypotensive anesthesia, arthroscopic pump) means of bleeding control have been used with varying degrees of success. However, the simplest technique of all has been ignored until now. Application of Bernoulli's Principle to achieve turbulence control by means of digital pressure over a leaking portal can quickly and easily enhance visualization.

SLAP lesions in the overhead athlete.

The authors report an 87% rate of return to preinjury levels of throwing in 54 baseball players and an 84% rate of return to preinjury performance levels in pitches after repair of type II SLAP lesions. The etiology, biomechanics, surgical repair, and rehabilitation are discussed in detail.

The evolution of clinical applications of biodegradable implants in arthroscopic surgery.

Arthroscopic surgery is the most recent orthopaedic discipline to embrace biodegradable implant technology. Osteochondral fractures have been shown to be amenable to arthroscopic fixation with biodegradable pins. The areas of most recent interest have been biodegradable interference screw fixation for ACL reconstruction in the knee, biodegradable suture anchors for rotator cuff repair and capsulolabral repair in the shoulder. Biodegradable implants have allowed a paradigm shift away from bionic (mechanical replacement) engineering and toward true biologic solutions to reconstructive problems in arthroscopic surgery.

Traumatic glenohumeral bone defects and their relationship to failure of arthroscopic Bankart repairs: significance of the inverted-pear glenoid and the humeral engaging Hill-Sachs lesion.

PURPOSE: Our goal was to analyze the results of 194 consecutive arthroscopic Bankart repairs (performed by 2 surgeons with an identical suture anchor technique) in order to identify specific factors related to recurrence of instability. TYPE OF STUDY: Case series. MATERIALS AND METHODS: We analyzed 194 consecutive arthroscopic Bankart repairs by suture anchor technique performed for traumatic anterior-inferior instability. The average follow-up was 27 months (range, 14 to 79 months). There were 101 contact athletes (96 South African rugby players and 5 American football players). We identified significant bone defects on either the humerus or the glenoid as (1) "inverted-pear" glenoid, in which the normally pear-shaped glenoid had lost enough anterior-inferior bone to assume the shape of an inverted pear; or (2) "engaging" Hill-Sachs lesion of the humerus, in which the orientation of the Hill-Sachs lesion was such that it engaged the anterior glenoid with the shoulder in abduction and external rotation. RESULTS: There were 21 recurrent dislocations and subluxations (14 dislocations, 7 subluxations). Of those 21 shoulders with recurrent instability, 14 had significant bone defects (3 engaging Hill-Sachs and 11 inverted-pear Bankart lesions). For the group of patients without significant bone defects (173 shoulders), there were 7 recurrences (4% recurrence rate). For the group with significant bone defects (21 patients), there were 14 recurrences (67% recurrence rate). For contact athletes without significant bone defects, there was a 6.5% recurrence rate, whereas for contact athletes with significant bone defects, there was an 89% recurrence rate. CONCLUSIONS: (1) Arthroscopic Bankart repairs give results equal to open Bankart repairs if there are no significant structural bone deficits (engaging Hill-Sachs or inverted-pear Bankart lesions). (2) Patients with significant bone deficits as defined in this study are not candidates for arthroscopic Bankart repair. (3) Contact athletes without structural bone deficits may be treated by arthroscopic Bankart repair. However, contact athletes with bone deficiency require open surgery aimed at their specific anatomic deficiencies. (4) For patients with significant glenoid bone loss, the surgeon should consider reconstruction by means of the Latarjet procedure, using a large coracoid bone graft.

Articular arc length mismatch as a cause of failed bankart repair.

The purpose of this article is to recognize an often overlooked cause of failed anterior stabilization procedures of the shoulder. Hill-Sachs lesions are common occurrences after anterior dislocation. But despite the frequency of occurrence, they are commonly not addressed in the treatment of recurrent anterior dislocation. The Hill-Sachs lesion produces a shortened rotational arc length of the humeral head on the glenoid; any engagement of the defect with the glenoid produces a sensation in the patient of subluxation/dislocation. However, instead of subluxation/dislocation, the sensation may be caused by mismatch between the articular arc length of the humeral head and the glenoid. The literature concerning the Hill-Sachs lesion and its association with recurrent dislocation has been reviewed. There is no recognition in the literature of this articular arc length mismatch as a cause of failed anterior stabilization procedures. We present a case in which a Hill-Sachs lesion was the cause of a perceived recurrent subluxation/dislocation of the shoulder.

Knot security in simple sliding knots and its relationship to rotator cuff repair: how secure must the knot be?

We sought to determine which simple sliding knot configurations would have adequate strength for rotator cuff repair. Four knot configurations were tied with both No. 1 polydioxanone suture and No. 2 Ethibond suture (Ethicon, Somerville, NJ) using 3 different tying techniques: hand-tie, standard knot pusher, and cannulated double-diameter knot pusher. The knots were then tested to failure on a materials testing system. The weakest standard knot configuration was S=S=S=S. The other 3 knot configurations (S//S//S//S, SxSxSxS, and S//xS//xS//xS) generally failed in the 35 to 50 N range. Ultimate strength in this range can be shown to be adequate to withstand, without suture failure, a maximal contraction of a repaired rotator cuff tear within the rotator crescent, assuming certain conditions are met (suture anchors placed 1 cm apart, 2 sutures per anchor). More complex knots are not necessary for adequate knot security. However, the same configuration with only 1 suture per anchor will not be strong enough because the suture will fail under maximum physiological load. This study shows that we can predict the adequacy of a given knot configuration under maximum physiological loading conditions.

The pitcher's mound: a late sequela of posterior type II SLAP lesions.

Three patients with long-standing disabling shoulder pain underwent arthroscopic examination. Two of the 3 had preoperative magnetic resonance imaging scans showing complete rotator cuff tears confirmed at surgery. The third patient was found to have a partial-thickness bursal surface cuff tear. In addition, each patient was found to have a quite prominent posterior superior glenoid osteophyte located beneath an unstable type II SLAP lesion.

Shoulder injuries in overhead athletes. The "dead arm" revisited.

The following statements summarize this article: Three distinct categories of Type 2 SLAP lesions exist: (1) anterior, (2) posterior, and (3) combined anteroposterior. Posterior Type 2 SLAP lesions have distinct clinical and anatomic features that distinguish them from anterior Type 2 SLAP lesions. Posterior and combined Type 2 SLAP lesions can be disabling to overhead-throwing athletes because of posterosuperior instability and anteroinferior pseudolaxity. The Jobe relocation test is positive with posterosuperior pain in patients with posterior or combined anterior-posterior Type 2 SLAP lesions and is negative in patients with anterior Type 2 SLAP lesions. Rotator cuff tears are frequently associated with posterior or combined anterior-posterior SLAP lesions, are lesion-location specific, and typically begin from inside the joint as undersurface tears. Repair of posterior SLAP lesions can return overhead-throwing athletes to full overhead athletic functioning. The peel-back mechanism is a likely cause of posterior Type 2 SLAP lesions. To securely repair the posterosuperior labrum to resist torsional peel-back, sulure anchors must be placed posterior to the biceps at the corner of the glenoid. The repair must be protected against external rotation past 0 degree for 3 weeks to avoid undue premature torsional stresses on the repair from the peel-back mechanism. A tight posteroinferior capsule predisposes to Type 2 SLAP lesions in overhead athletes. Shoulders at risk for the dead arm syndrome have a marked loss of internal rotation caused by contracture of the posteroinferior capsule such that less than a 180 degrees arc of rotation is achieved with the arm abducted 90 degrees (the 180 degrees rule). Type 2 SLAP lesions that cause the dead arm syndrome in overhead-throwing athletes are most likely acceleration injuries that occur in late cocking rather than deceleration injuries in follow-through. Rehabilitation of athletes with the dead arm syndrome must include the entire kinetic chain. The root cause of the dead arm syndrome is the Type 2 SLAP lesion.

A stepwise approach to arthroscopic rotator cuff repair based on biomechanical principles.

SUMMARY: The author has previously elucidated and advocated various biomechanical principles for application in rotator cuff repair. This article is an attempt to link all these concepts together into a unified stepwise approach to arthroscopic rotator cuff repair that will maximize the strength of the repair for all tear configurations.

How to switch posts without rethreading when tying half-hitches.

Arthroscopically tied stacked half-hitch knots and sliding knots are best locked with half-hitches on alternating posts. It is possible to switch posts without rethreading the suture through the knot tier by flipping the half-hitch. This article describes extra- and intra-articular techniques for flipping half-hitches to switch posts. The post switching is most easily accomplished by transforming the half-hitch to an intermediate flat knot with symmetrical throws. This intermediate step is imperceptible when the sequence of actions is rapid. An over-under half-hitch becomes an under-over half-hitch when the post is switched.

Orthopaedic applications for PLA-PGA biodegradable polymers.

Biodegradable polymers, especially those belonging to the family of polylactic acid (PLA) and polyglycolic acid (PGA), play an increasingly important role in orthopaedics. These polymers degrade by hydrolysis and enzymatic activity and have a range of mechanical and physical properties that can be engineered appropriately to suit a particular application. Their degradation characteristics depend on several parameters including their molecular structure, crystallinity, and copolymer ratio. These biomaterials are also rapidly gaining recognition in the fledging field of tissue engineering because they can be fashioned into porous scaffolds or carriers of cells, extracellular matrix components, and bioactive agents. Although their future appears to be bright, several questions regarding the biocompatibility of these materials linger and should be addressed before their wide-scale use. In the context of musculoskeletal tissue, this report provides a comprehensive review of properties and applications of biodegradable PLA/PGA polymers and their copolymers. Of special interest are orthopaedic applications, biocompatibility studies, and issues of sterilization and storage of these versatile biomaterials. Also discussed is the fact that terms such as PLA, PGA, or PLA-PGA do not denote one material, but rather a large family of materials that have a wide range of differing bioengineering properties and concomitant biological responses. An analysis of some misconceptions, problems, and potential solutions is also provided.

Loop security as a determinant of tissue fixation security.

Secure arthroscopic repair of rotator cuff tears and Bankart lesions requires tight knots (knot security). Equally important, but usually overlooked, is the tightness of the suture loop (loop security). This study compared loop security in knots tied with No. 1 PDS suture using three different methods: (1) hand-tied, (2) single-hole standard knot pusher, and (3) cannulated double-diameter knot pusher. The results of this study show that the double-diameter knot pusher maintained tight suture loops that were equivalent in circumference to hand-tied loops and were significantly tighter than suture loops tied with a standard single-hole knot pusher. This study highlights the fact that loop security is equally important to knot security in tissue fixation.

Type II SLAP lesions: three subtypes and their relationships to superior instability and rotator cuff tears.

One hundred two type II SLAP lesions without associated anterior instability, Bankart lesion, or anterior inferior labral pathology were surgically treated under arthroscopic control. There were three distinct type II SLAP lesions based on anatomic location: anterior (37%), posterior (31%), and combined anterior and posterior (31%). Preoperatively, the Speed and O'Brien tests were useful in predicting anterior lesions, whereas the Jobe relocation test was useful in predicting posterior lesions. Rotator cuff tears were present in 31% of patients and were found to be lesion-location specific. In posterior and combined anterior-posterior lesions, a drive-through sign was always present (despite absence of anterior-inferior labral pathology or a Bankart lesion) and was eliminated by repair of the posterior component of the SLAP lesion. We conclude that SLAP lesions with a posterior component develop posterior-superior instability that manifests itself by a secondary anterior-inferior pseudolaxity (drive-through sign), and that chronic superior instability leads to secondary lesion-location-specific rotator cuff tears that begin as partial thickness tears from inside the joint.

The peel-back mechanism: its role in producing and extending posterior type II SLAP lesions and its effect on SLAP repair rehabilitation.

A previously undescribed mechanism of injury for posterior Type II SLAP lesions is described. The primary feature of this mechanism is a torsional peel-back of the posterosuperior labrum. Secure fixation by posterior-superior placement of suture anchors into the posterosuperior corner of the glenoid is essential. The repair must be protected against torsional peel-back forces by avoiding external rotation beyond 0 degrees for 3 weeks.