Rotator Cuff Augmentation: Its Role and Best Practices.

Rotator cuff tears are a common source of pain and impairment in the shoulder. Healing of the rotator cuff tendons following repair has been associated with improved patient outcomes. While there have been many technical improvements in surgical techniques for rotator cuff repair, failure rates are still surprisingly high. Augmentation of these repairs has been shown to help with fixation biomechanics as well as healing rates. The described types of augments include autograft, allograft, xenograft, and synthetic options. This report reviews the commonly available types of augments and some of the outcomes associated with their use.

Suture spanning augmentation of single-row rotator cuff repair: a biomechanical analysis.

BACKGROUND: This in vitro study evaluated the biomechanical benefit of adding spanning sutures to single-row rotator cuff repair. METHODS: Mechanical testing was performed to evaluate 9 pairs of cadaveric shoulders with complete rotator cuff repairs, with a single-row technique used on one side and the suture spanning technique on the other. The spanning technique included sutures from 2 lateral anchors securing tendon near the musculotendinous junction, spanning the same anchor placement from single-row repair. The supraspinatus muscle was loaded to 100 N at 0.25 Hz for 100 cycles, followed by a ramp to failure. Markers and a video tracking system measured anterior and posterior gap formation across the repair at 25-cycle intervals. The force at which the stiffness decreased by 50% and 75% was determined. Data were compared using paired t-tests. RESULTS: One single-row repair failed at <25 cycles. Both anterior and posterior gap distances tended to be 1 to 2 mm larger for the single-row repairs than for the suture spanning technique. The difference was statistically significant at all cycles for the posterior gap formation (P ≤ .02). The trends were not significant for the anterior gap (P ≥ .13). The loads at which the stiffness decreased by 50% and 75% did not differ significantly between the 2 types of repair (P ≥ .10). CONCLUSIONS: The suture spanning technique primarily improved posterior gap formation. Decreased posterior gap formation could reduce failure rates for rotator cuff repair.

Arthroscopic posterior labral repair and capsular shift with a lateralized posterior portal.

Arthroscopic techniques for posterior shoulder subluxation with labral injuries in athletes have shown good results. The difficulty with the procedure is gaining appropriate access to the posteroinferior quadrant of the glenoid at a steep enough angle that allows for safe anchor placement. Various portals have been described that can be used as accessory portals for anchor placement. Although the use of additional portals to create appropriate access to the joint is always encouraged, preoperative planning can minimize the need for their use. The video shows a simple technique for posterior labral repair with capsular plications through a lateralized posterior portal in the lateral decubitus position. This technique allows the surgeon to address posterior labral tears and capsular laxity without the need for accessory portals.

Tension level during preconditioning influences hamstring tendon graft properties.

BACKGROUND: Hamstring tendon grafts used for anterior cruciate ligament reconstruction are preconditioned to reduce the influence of viscoelasticity on the stiffness and tension. HYPOTHESIS: Increasing the tension applied during preconditioning will decrease the loss of tension and stiffness due to viscoelasticity. STUDY DESIGN: Controlled laboratory study. METHODS: Six quadruple-strand hamstring tendon grafts were tested twice in vitro with 2 tension levels applied during preconditioning. The grafts were preconditioned at 80 N or 160 N, followed by 15 minutes of relaxation, and subsequently loaded to 80 N to represent application of initial tension. After 5 minutes of relaxation, the tension was recorded and the stiffness was measured over 0.06 mm of displacement. The tension and stiffness measurements were repeated 3 hours later. The data were compared between the 2 preconditioning levels with a 2-way repeated-measures analysis of variance. RESULTS: Graft tension and stiffness were significantly larger (P < .05) for 160 N during preconditioning. For 80 N, the average tension at 5 minutes and 3 hours was 40 N and 21 N, respectively, compared with 50 N and 30 N, respectively, for 160 N. For 80 N, the average stiffness at 5 minutes and 3 hours was 152 N/mm and 124 N/mm, respectively, compared with 173 N/mm and 146 N/mm, respectively, for 160 N. CONCLUSION: Increasing the tension applied to hamstring tendon grafts during preconditioning can decrease the postoperative loss of tension and stiffness due to viscoelasticity. CLINICAL RELEVANCE: The increased graft tension and stiffness could reduce postoperative knee laxity.

In vitro comparison of tension and stiffness between hamstring tendon and patella tendon grafts.

Following anterior cruciate ligament reconstruction, grafts relax and warm from the temperature of the operating room to body temperature. The current study compared graft tension and stiffness between patella tendon and hamstring tendon grafts. Six quadruple strand hamstring tendon grafts and six patella tendon grafts were preconditioned and loaded to 105 N while at 20 degrees C. Graft tension and stiffness were measured after 15 min, after an additional 4 h, and after increasing the temperature to 34 degrees C. A two-way repeated-measures analysis of variance and a post hoc test were used to compare the measurements between the two types of graft and identify significant (p < 0.05) changes for each type of graft. Tension was significantly larger for the patella tendon grafts, although the stiffness values were not significantly different (p > 0.8). For both types of graft, tension and stiffness decreased significantly with time and the temperature increase. The lowest tension and stiffness measurements were 50 +/- 11 N and 129 +/- 35 N/mm, respectively, for the patella tendon grafts, compared to 18 +/- 5 N and 115 +/- 11 N/mm, respectively, for the hamstring tendon grafts. Both types of graft lose tension to relaxation and a temperature increase, but the tension loss is larger for hamstring tendon grafts.

Assessment of pain relief provided by interscalene regional block and infusion pump after arthroscopic shoulder surgery.

PURPOSE: This study was performed to evaluate the efficacy of interscalene regional blocks and infusion pumps for postoperative pain control after arthroscopic subacromial decompression with or without arthroscopic rotator cuff repair. METHODS: Seventy-six patients were included in the prospective study. Participants were randomized into 4 treatment groups: (1) interscalene regional block, (2) infusion pump with 0.5% bupivacaine, (3) interscalene block combined with an infusion pump containing 0.5% bupivacaine, and (4) interscalene block combined with an infusion pump containing 0.9% saline solution. The interscalene regional block was performed with a nerve stimulator. Infusion pump catheters were positioned in the subacromial space. Visual analog scale (VAS) data were collected preoperatively, at 1 and 2 hours postoperatively, and daily for an additional 6 days postoperatively. An analysis of variance with a Student-Newman-Keuls post hoc test was used to identify statistically significant (P < .05) differences in VAS scores between the groups at each time point. Percentages of patients who took medication for pain management in the recovery room were compared between the 4 groups by use of chi(2) analysis. RESULTS: Significant differences were noted in VAS scores postoperatively. Group 2 (pump only) had significantly higher scores than all other groups for the first 2 hours. Furthermore, group 4 (block and pump filled with saline solution) had significantly lower VAS scores than group 1 (block only) at 1 hour. This difference was no longer significant by the second hour. The percentage of patients who required oral narcotics or intravenous pain medication was significantly larger for group 2 than for the other groups. CONCLUSIONS: The interscalene regional block provided more pain relief than infusion pumps immediately after arthroscopic shoulder surgery. Infusion pumps did not significantly reduce pain levels after the blocks wore off. LEVEL OF EVIDENCE: Level II, prospective comparative therapeutic study.

Elbow function after repair of the distal biceps brachii tendon with a two-incision approach.

A modified Boyd-Anderson 2-incision approach is commonly used to repair the distal biceps tendon after avulsion from the radial tuberosity. Using suture anchors for fixation instead of a bone trough simplifies the procedure. This retrospective study enrolled 32 patients who underwent surgical repair of the distal biceps tendon with a 2-incision approach and 2 suture anchors. The mean postoperative follow-up was 42 months. Elbow strength, endurance, and range of motion for flexion, pronation, and supination were measured for each arm. For each strength and endurance measurement, the mean for the involved arm was at least 95% of that for the uninvolved arms. The largest flexion, pronation, and supination deficits for an injured arm, as compared with the uninjured arm, were 9 degrees, 15 degrees, and 16 degrees, respectively. A 2-incision approach for distal biceps tendon repair with suture anchor fixation can restore elbow function and satisfy patients.

Viscoelasticity and temperature variations decrease tension and stiffness of hamstring tendon grafts following anterior cruciate ligament reconstruction.

BACKGROUND: Hamstring tendon grafts used for anterior cruciate ligament reconstruction are typically harvested early in the surgical procedure and are preconditioned prior to reimplantation. Postoperatively, the grafts undergo stress relaxation and warm from the temperature of the operating room to body temperature. The hypothesis of this study was that the tension within semitendinosus and gracilis tendon grafts and the stiffness of the grafts significantly decrease postoperatively because of both stress relaxation and an increase in temperature. METHODS: Double-strand grafts were created from six semitendinosus tendons and six gracilis tendons harvested from cadaver specimens. The grafts were loaded to 65 N while at operating-room temperature (20 degrees C). After fifteen minutes of stress relaxation, graft tension was measured and the grafts were stretched by 0.1 mm to determine stiffness. The tension and stiffness measurements represented graft properties immediately following reconstruction. Additional tension and stiffness measurements were made following three hours of stress relaxation and after increasing the temperature to the body temperature at the knee (34 degrees C). Both types of graft were examined for differences in stiffness and tension due to stress relaxation and the temperature increase. RESULTS: For both types of graft, the tension and stiffness decreased following stress relaxation to approximately 50% and 80%, respectively, of the value immediately after reconstruction. Increasing the temperature decreased the tension and stiffness further to approximately 40% and 70%, respectively, of the value after reconstruction for both types of graft. All changes in tension and stiffness were significant (p < 0.01). CONCLUSIONS: Graft tension and stiffness achieved immediately following reconstruction are not maintained postoperatively because of stress relaxation and a temperature increase. This could lead to increased knee laxity.

Locking plates improve torsional resistance in the stabilization of three-part proximal humeral fractures.

This study quantified the torsional resistance provided by locking plates and angled blade plates used to stabilize proximal humeral fractures. Three-part proximal humeral fractures were created in 6 pairs of cadaveric humeri. One specimen of each pair was reconstructed with a proximal humeral locking plate, whereas the other specimen was reconstructed with an angled blade plate. An external rotation torque, varying from 0 to 5 N-m, was applied to the humeral head until the head rotated 30 degrees or 10,000 loading cycles were applied. The mean initial torsional stiffness was significantly larger for the locking plates (0.99 N-m/degree) than for the blade plates (0.59 N-m/degree). For each pair, the maximum rotation was larger for the blade plate than for the locking plate. For this in vitro model of a reconstructed 3-part proximal humeral fracture, the locking plate provided better torsional fatigue resistance and stiffness than the blade plate.

Structural properties of lateral collateral ligament reconstruction at the fibular head.

BACKGROUND: Anatomical reconstruction of a ruptured lateral collateral ligament using allograft tissue secured within the fibular head with an interference screw has been described. HYPOTHESIS: Interference fixation at the fibular head does not reproduce the strength of the intact ligament. STUDY DESIGN: Controlled laboratory study. METHODS: Ten intact lateral collateral ligaments were tested to failure. The distal fixation of 11 ligaments reconstructed with a graft including a bone plug and 11 ligaments reconstructed with a graft without a bone plug were also tested. RESULTS: The reconstructed ligaments consistently failed at the fibular head. The intact specimens predominately failed through ligament rupture. The mean strength and stiffness values were 460 +/- 163 N and 82 +/- 25 N/mm, respectively, for the intact ligaments, 113 +/- 40 N and 36 +/- 10 N/mm, respectively, for reconstruction with a bone plug, and 135 +/- 81 N and 34 +/- 14 N/mm, respectively, for reconstruction without a bone plug. The strength and stiffness were significantly (P < .05) greater for the intact ligaments than for either reconstruction group. The variation in strength was significantly larger for reconstruction without a bone plug than for reconstruction with a bone plug. CONCLUSION: Tension applied to lateral collateral ligaments reconstructed using fibular interference fixation should be limited immediately after surgery. Soft tissue fixation should be employed with care because of the inconsistency in the failure strength. CLINICAL RELEVANCE: Although fibular interference fixation is increasingly being described in the literature, the properties of reconstructed lateral collateral ligaments have not previously been quantified.

Simplified arthroscopic suture passing using a suture loop.

Arthroscopic procedures for shoulder pathology are becoming more popular. Passing braided nonabsorbable suture for repair of intra-articular tissue can be technically difficult because advancing this suture through tissue is a 2-step process. The use of a suture loop with Spectrum suture hooks (Linvatec, Largo, FL) simplifies braided suture passing, and eliminates the use of expensive suture shuttles. This technique simplifies the use of nonabsorbable suture in arthroscopic shoulder procedures.