Resorbable Bioinductive Collagen Implant Is Cost Effective in the Treatment of Rotator Cuff Tears.

Purpose: This study was conducted to investigate whether the use of resorbable bioinductive collagen implant (RBI) in addition to conventional rotator cuff repair (conventional RCR) is cost-effective when compared to conventional RCR alone, in the treatment of full-thickness rotator cuff tears (FT RCT). Methods: We developed a decision analytic model to compare the expected incremental cost and clinical consequences for a cohort of patients with FT RCT. The probabilities for healing or failure to heal (retear) were estimated from the published literature. Implant and healthcare costs were estimated from a payor's perspective in 2021 U.S. prices. An additional analysis included indirect cost estimations (e.g., productivity losses). Sensitivity analyses explored the effect of tear size, as well as the impact of risk factors. Results: The base case analysis demonstrated that resorbable bioinductive collagen implant + conventional rotator cuff repair results in incremental costs of $232,468 and an additional 18 healed RCTs per 100 treated patients over 1 year. The estimated incremental cost-effectiveness ratio (ICER) is $13,061/healed RCT compared to conventional RCR alone. When return to work was included in the model, RBI + conventional RCR was found to be cost saving. Cost-effectiveness improved with tear size with the largest benefit seen in massive tears compared to large tears, as well as patients at higher risk of retearing. Conclusions: This economic analysis demonstrated that RBI + conventional RCR delivered improved healing rates at a marginal increase in costs when compared to conventional RCR alone and is, therefore, cost-effective in this patient population. Considering indirect costs, RBI + conventional RCR resulted in lower costs compared to conventional RCR alone and is, therefore, deemed to be cost saving. Level of Evidence: Level IV, economic analysis.

Characteristics of Orthopaedic Sports Medicine Fellowship Directors.

BACKGROUND: No study in the orthopaedic literature has analyzed the demographic characteristics or surgical training of sports medicine fellowship directors (FDs). Objective determinations as to what makes a physician qualified for this leadership position remain unclear; thus, it is important to identify these qualities as future physicians look to fill these roles. PURPOSE: To illustrate characteristics common among sports medicine FDs. STUDY DESIGN: Cross-sectional study. METHODS: The 2020 Accreditation Council for Graduate Medical Education Fellowship Directory was used to identify the FDs for all orthopaedic sports medicine fellowship programs in the United States. The characteristics and educational background data for FDs were gathered by 2 independent reviewers from up-to-date curricula vitarum, Web of Science, and institutional biographies and consolidated into 1 database. Data points gathered included age, sex, residency/fellowship training location and graduation year, name of current institution, length of time at current institution, time since training completion until being appointed FD, length of time in current FD role, and personal research H-index. RESULTS: We identified 90 current orthopaedic sports medicine FDs. The mean Scopus H-index was 24.1 (median, 17). The mean age of FDs was 55.4 years; 87 of 90 (96.7%) were male and 3 (3.3%) were female; and 79/90 (87.8%) were White and 3/90 (3.3%) were African-American. The mean time to complete residency was 5.1 years (range, 5.0-6.0 years), and the most attended residency programs were the Hospital for Special Surgery (n = 9), the Harvard Combined Orthopaedic Residency Program (n = 5), and Duke University Medical Center (n = 4). The mean time required to complete a fellowship was 1.1 years (range, 1.0-2.0 years), and the fellowship programs that produced the most future FDs were the American Sports Medicine Institute (n = 11), the Steadman Hawkins Clinic (Vail) (n = 8), the Kerlan-Jobe Orthopaedic Clinic (n = 7), and the Hospital for Special Surgery (n = 7). The mean time from completion of fellowship to appointment as a FD was 12.8 years (range, 1-39 years). CONCLUSION: Women and minority groups are largely underrepresented among leadership positions in the field of orthopaedic sports medicine.

Isolated bioinductive repair of partial-thickness rotator cuff tears using a resorbable bovine collagen implant: two-year radiologic and clinical outcomes from a prospective multicenter study.

BACKGROUND: Current surgical treatment options for partial-thickness tears (eg, takedown and repair, in situ repair) are limited by the degenerative nature of the underlying tendon and may require extensive intervention that can alter the anatomic footprint. The complexity of available techniques to address these issues led to the development of a resorbable collagen implant, which can be used to create a bioinductive repair of partial-thickness tears. METHODS: We prospectively enrolled 33 patients with chronic, degenerative, intermediate-grade (n = 12), or high-grade (n = 21) partial-thickness tears (11 articular, 10 bursal, 4 intrasubstance, and 8 hybrid) of the supraspinatus tendon in a multicenter study. After arthroscopic subacromial decompression without a traditional rotator cuff repair, a bioinductive implant was secured over the bursal surface of the tendon. Clinical outcomes were assessed using American Shoulder and Elbow Surgeons (ASES) and Constant-Murley scores (CMS) preoperatively and at 3 months, 1 year, and 2 years postoperatively. Magnetic resonance imaging was performed to assess postoperative tendon healing and thickness at the original tear site. RESULTS: At 2-year follow-up, mean ASES and CMS scores improved both clinically and statistically at 1 and 2 years, compared with baseline, for intermediate- and high-grade tears. There was magnetic resonance imaging evidence of new tissue fill-in within the original baseline tear in 100% of the intermediate-grade tears and 95% of the high-grade tears. In 90.9% of the intermediate-grade tears and 84.2% of the high-grade tears, this new tissue fill-in represented at least an additional 50% of the volume of the initial lesion. From baseline to 2-year follow-up, the mean tendon thickness increased by 1.2 mm (standard deviation, 1.3; P = .012) and 1.8 mm (standard deviation, 2.2; P = .003) in the intermediate- and high-grade tears, respectively. The analysis of tear grade and location revealed no statistically significant difference in the change in mean tendon thickness at any time point. One patient with a high-grade articular lesion demonstrated progression to a full-thickness tear; however, the patient was noncompliant and the injury occurred while shoveling snow 1 month after surgery. Neither tear location nor treatment of bicep pathology affected the ASES or CMS scores at any follow-up point. No serious adverse events related to the implant were reported. CONCLUSION: Final results from this 2-year prospective study indicate that the use of this resorbable bovine collagen implant for isolated bioinductive repair of intermediate- and high-grade partial-thickness rotator cuff tears of the supraspinatus is safe and effective, regardless of tear grade and location.

A prospective study assessing the political advocacy of American Shoulder and Elbow Surgeons members.

BACKGROUND: This study assessed the current political standings and active political engagement of American Shoulder and Elbow Surgeons (ASES) members along with the political process as it relates to health care policy. METHODS: This survey study involved 552 ASES members. The survey was open for 2 weeks. Responses were received from 254 of the 552 members (46%), and their answers were analyzed. RESULTS: Six (2%) of the responding members were solo practitioners, 100 (39%) belonged to a private practice, 106 (42%) were providers at academic institutions or residency training programs, 25 (10%) were employed by a hospital, and 17 (7%) categorized themselves as other. Email was the preferred method of communication. Of all responding members, 110 (43%) stated they had contributed to the American Academy of Orthopaedic Surgery Political Advocacy Committee in the last 12 months. Four (10%) of the responding members have a relationship with an elected official, and 220 (87%) would be willing to become a key contact and reach out to a legislator. CONCLUSION: Moving forward, this survey can be used to better shape the political advocacy efforts of the ASES and potentially other subspecialty societies. The response that "a high percentage of members would like to be more involved" suggests the need for a program to help further educate and facilitate the membership on political advocacy.

Surgical Technique for Release of Anterior Interval Scarring of the Knee After Anterior Cruciate Ligament Reconstruction.

Postoperative scarring is a known complication after arthroscopic anterior ligament reconstruction of the knee. The anterior interval of the knee has been previously identified as a common location for anterior scar formation. The anterior interval is defined as the space between the infrapatellar fat pad and the anterior border of the tibia. Patients with anterior interval scarring often present with lack of terminal knee extension, anterior knee pain, decreased patellar mobility, and quadriceps atrophy. The goal of this paper is to describe the technique for anterior interval release of the knee.

Radiologic and clinical evaluation of a bioabsorbable collagen implant to treat partial-thickness tears: a prospective multicenter study.

BACKGROUND: Treatment of partial-thickness cuff tears remains controversial. Although conservative therapy may treat symptoms, these defects do not spontaneously heal and conversion to a full-thickness lesion with subsequent repair may alter the tendon footprint. The ability to induce new tissue formation and limit tear progression in intermediate- and high-grade partial-thickness tears without surgical repair may represent a significant advancement in the treatment paradigm for these lesions. METHODS: We prospectively enrolled 33 patients with chronic, degenerative, intermediate-grade (n = 12) or high-grade (n = 21) partial-thickness tears (11 articular, 10 bursal, 4 intrasubstance, and 8 hybrid) of the supraspinatus tendon in a multicenter study. Following arthroscopic subacromial decompression without repair, a bioinductive implant was attached over the bursal surface of the tendon. Clinical outcomes were assessed using American Shoulder and Elbow Surgeons and Constant-Murley scores preoperatively and at 3 and 12 months postoperatively. Magnetic resonance imaging was performed to assess postoperative tendon healing and thickness at the original tear site. RESULTS: At 1-year follow-up, clinical scores improved significantly (P <.0001) and the mean tendon thickness increased by 2.0 mm (P <.0001). Magnetic resonance imaging evidence of complete healing was found in 8 patients and a considerable reduction in defect size was shown in 23, whereas 1 lesion remained stable. In 1 noncompliant patient with a high-grade articular lesion, progression to a full-thickness tear occurred while shoveling snow 1 month after surgery. No serious adverse events related to the implant were reported. CONCLUSIONS: Arthroscopic implantation of a bioinductive collagen scaffold is a safe and effective treatment for intermediate- to high-grade partial-thickness rotator cuff tears of the supraspinatus tendon.

Tissue-engineered augmentation of a rotator cuff tendon using a reconstituted collagen scaffold: a histological evaluation in sheep.

To determine if an absorbable collagen scaffold of high porosity would allow rapid tissue in-growth and permit the functional maturation and alignment of tendon-like tissue, scaffolds were sutured to the superficial surface of the infraspinatus tendons of adult sheep. Histology demonstrated complete ingrowth with fibrovascular tissue by 6 weeks and by 12 weeks the scaffold had induced the formation of a layer of dense, regularly-oriented collagenous tissue which significantly increased the thickness of the native tendon. This new tissue was well-integrated into the host tissues at both the bone interface and along the length of the tendon. At 26 weeks the scaffold was completely absorbed leaving a stable layer of mature tendon-like tissue over the surface of the host tendon which was still present at 52 weeks. The use of a reconstituted collagen scaffold consistently increased the thickness of a rotator cuff tendon by inducing the formation of a well-integrated and mature tendon-like tissue.

Quadriceps tendon injuries in national football league players.

BACKGROUND: Distal quadriceps tendon tears are uncommon injuries that typically occur in patients older than 40 years of age, and they have a guarded prognosis. Predisposing factors, prodromal findings, mechanisms of injury, treatment guidelines, and recovery expectations are not well described in high-level athletes. HYPOTHESIS: Professional American football players with an isolated tear of the quadriceps tendon treated with timely surgical repair will return to their sport. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Fourteen unilateral distal quadriceps tendon tears were identified in National Football League (NFL) players from 1994 to 2004. Team physicians retrospectively reviewed training room and clinic records, operative notes, and imaging studies for each of these players. Data on each player were analyzed to identify variables predicting return to play. A successful outcome was defined as returning to play in regular-season NFL games. RESULTS: Eccentric contraction of the quadriceps was the most common mechanism of injury, occurring in 10 players. Only 1 player had antecedent ipsilateral extensor mechanism symptoms. Eleven players had a complete rupture of the quadriceps tendon, and 3 had partial tears. There were no associated knee injuries. All ruptures were treated with surgical repair, 1 of which was delayed after failure of nonoperative treatment. Fifty percent of players returned to play in regular-season NFL games. There was a trend toward earlier draft status for those who returned to play compared with those who did not (draft round, 3.1 ± 2.5 vs. 6.0 ± 2.9, respectively; P = .073). For those who returned to play, the average number of games after injury was 40.9 (range, 12-92). CONCLUSION: Quadriceps tendon tears are rare in professional American football players, and they usually occur from eccentric load on the extensor mechanism. Prodromal symptoms and predisposing factors are usually absent. Even with timely surgical repair, there is a low rate of return to play in regular-season games. There is a trend toward early draft rounds for those who successfully return to play.

National Football League athletes' return to play after surgical reattachment of complete proximal hamstring ruptures.

Although hamstring strains are common among professional football players, proximal tendon avulsions are relatively rare. Surgical repair is recommended, but there is no evidence on professional football players return to play (RTP). We hypothesized that surgical reattachment of complete proximal hamstring ruptures in these athletes would enable successful RTP. Ten proximal hamstring avulsions were identified in 10 National Football League (NFL) players between 1990 and 2008. Participating team physicians retrospectively reviewed each player's training room and clinical records, operative notes, and imaging studies. The ruptures were identified and confirmed with magnetic resonance imaging. Of the 10 injuries, 9 had palpable defects. Each of the ruptures was managed with surgical fixation within 10 days of injury. All of the players reported full return of strength and attempted to resume play at the beginning of the following season, with 9 of the 10 actually returning to play. However, despite having no limitations related to the surgical repair, only 5 of the 10 athletes played in more than 1 game. Most NFL players who undergo acute surgical repair of complete proximal hamstring ruptures are able to RTP, but results are mixed regarding long-term participation. This finding may indicate that this injury is a marker for elite-level physical deterioration.

Recommendations of the national football league physician society task force on the use of toradol(®) ketorolac in the national football league.

Ketorolac tromethamine (Toradol(®)) is a non-steroidal anti-inflammatory drug that has potent analgesic and anti-inflammatory properties. It can be administered orally, intravenously, intramuscularly, or via a nasal route. Ketorolac injections have been used for several years in the National Football League (NFL), in both the oral and injectable forms, to treat musculoskeletal injuries and to prevent post-game soreness. In an attempt to determine the appropriate use of this medication in NFL players, the NFL Team Physician Society appointed a Task Force to consider the best available evidence as to how ketorolac should be used for pain management in professional football players. These treatment recommendations were established based on the available medical literature taking into consideration the pharmacokinetic properties of ketorolac, its accepted indications and contraindications, and the unique clinical challenges of the NFL. The Task Force recommended that 1) ketorolac should only be administered under the direct supervision and order of a team physician; 2) ketorolac should not be used prophylactically as a means of reducing anticipated pain either during or after participation in NFL games or practices and should be limited to those players diagnosed with an injury or condition and listed on the teams' injury report; 3) ketorolac should be given in the lowest effective therapeutic dose and should not be used in any form for more than 5 days; 4) ketorolac should be given in its oral preparation under typical circumstances; 5) ketorolac should not be taken concurrently with other NSAIDs or by those players with a history of allergic reaction to ketorolac, other NSAIDs or aspirin; and 6) ketorolac should not be used by a player with a history of significant gastrointestinal bleeding, renal compromise, or a past history of complications related to NSAIDs.

The cost-effectiveness of single-row compared with double-row arthroscopic rotator cuff repair.

BACKGROUND: Interest in double-row techniques for arthroscopic rotator cuff repair has increased over the last several years, presumably because of a combination of literature demonstrating superior biomechanical characteristics and recent improvements in instrumentation and technique. As a result of the increasing focus on value-based health-care delivery, orthopaedic surgeons must understand the cost implications of this practice. The purpose of this study was to examine the cost-effectiveness of double-row arthroscopic rotator cuff repair compared with traditional single-row repair. METHODS: A decision-analytic model was constructed to assess the cost-effectiveness of double-row arthroscopic rotator cuff repair compared with single-row repair on the basis of the cost per quality-adjusted life year gained. Two cohorts of patients (one with a tear of <3 cm and the other with a tear of ≥3 cm) were evaluated. Probabilities for retear and persistent symptoms, health utilities for the particular health states, and the direct costs for rotator cuff repair were derived from the orthopaedic literature and institutional data. RESULTS: The incremental cost-effectiveness ratio for double-row compared with single-row arthroscopic rotator cuff repair was $571,500 for rotator cuff tears of <3 cm and $460,200 for rotator cuff tears of ≥3 cm. The rate of radiographic or symptomatic retear alone did not influence cost-effectiveness results. If the increase in the cost of double-row repair was less than $287 for small or moderate tears and less than $352 for large or massive tears compared with the cost of single-row repair, then double-row repair would represent a cost-effective surgical alternative. CONCLUSIONS: On the basis of currently available data, double-row rotator cuff repair is not cost-effective for any size rotator cuff tears. However, variability in the values for costs and probability of retear can have a profound effect on the results of the model and may create an environment in which double-row repair becomes the more cost-effective surgical option. The identification of the threshold values in this study may help surgeons to determine the most cost-effective treatment.

A cost-effectiveness analysis comparing 3 anterior cruciate ligament graft types: bone-patellar tendon-bone autograft, hamstring autograft, and allograft.

BACKGROUND: Anterior cruciate ligament (ACL) reconstruction, despite being one of the most common surgical interventions, is also one of the least agreed upon surgeries when it comes to optimum graft choice. Three graft choices stand among the most widely used in this procedure: (1) bone-patellar tendon-bone autograft (BPTB), (2) quadruple hamstring tendon autograft (HS), and (3) allograft. HYPOTHESIS: Bone-patellar tendon-bone ACL reconstruction is the most cost-effective method of ACL reconstruction. STUDY DESIGN: Economic and decision analysis; Level of evidence, 2. METHODS: A simplified decision tree model was created with theoretical patients assigned equally to 1 of 3 ACL reconstruction cohorts based on graft type. These treatment arms were further divided into outcome arms based on probabilities from the literature. The terminal outcomes were assigned a health state/utility score and a societal cost. Utilities were calculated from real clinic patients via the time trade-off questionnaire. Costs were literature based. An incremental cost-effectiveness ratio of $50 000/quality-adjusted life year (QALY) was used as the threshold for cost-effectiveness. RESULTS: Hamstring tendon autograft was the least costly ($5375/surgery) and most effective (0.912) graft choice, dominating both BPTB and allograft reconstructions. Allograft was both the most costly and least effective strategy for the average patient undergoing ACL reconstruction. However, if baseline costs of BPTB could be reduced (by $500) or the effectiveness increased (anterior knee pain <15% or postoperative instability <7%), then BPTB became an incrementally cost-effective choice. In addition, if the effectiveness of HS could be reduced (instability >29% or revision rates >7%), then BPTB also became incrementally cost-effective. CONCLUSIONS: This model suggests that hamstring autograft ACL reconstruction is the most cost-effective method of surgery for the average patient with ACL deficiency. However, specific clinical scenarios that change postoperative probabilities of the different complications may sway surgeons to choose either allografts or BPTB. Cost-effectiveness analysis is not intended to replace individual clinician judgment but rather is intended to examine both the effectiveness and costs associated with theoretical groups undergoing specific multifactorial decisions.

Patellar tendon ruptures in National Football League players.

BACKGROUND: Although knee injuries are common among professional football players, ruptures of the patellar tendon are relatively rare. Predisposing factors, mechanisms of injury, treatment guidelines, and recovery expectations are not well established in high-level athletes. HYPOTHESIS: Professional football players with isolated rupture of the patellar tendon treated with timely surgical repair will return to their sport. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Twenty-four ruptures of the patellar tendon in 22 National Football League (NFL) players were identified from 1994 through 2004. Team physicians retrospectively reviewed training room and clinic records, operative notes, and imaging studies for each of these players. Player game statistics and draft status were analyzed to identify return to play predictors. A successful outcome was defined as participating in 1 regular-season NFL game. RESULTS: Eleven of the 24 injuries had antecedent symptoms. The most common mechanism of injury was an eccentric overload to a contracting extensor mechanism. Physical examination demonstrated a palpable defect in all players. Twenty-two were complete ruptures, and 2 were partial injuries. Three of the 24 cases had a concomitant anterior cruciate ligament (ACL) injury. In 19 of the 24 injuries, the player returned to participate in at least 1 game in the NFL. Players who returned were drafted, on average, in the fourth round, while those who failed to return to play were drafted, on average, in the sixth round. Of those players who returned to play, the average number of games played was 45.4, with a range of 1 to 142 games. CONCLUSION: Patellar tendon ruptures can occur in otherwise healthy professional football players without antecedent symptoms or predisposing factors. The most common mechanism of injury is eccentric overload. Close attention should be paid to stability examination of the knee given the not uncommon occurrence of concomitant ACL injury. Although this is usually a season-ending injury when it occurs in isolation, acute surgical repair generally produces good functional results and allows for return to play the following season. Players chosen earlier in the draft are more likely to return to play.

Treatment of magnetic resonance imaging-documented isolated grade III lateral collateral ligament injuries in National Football League athletes.

BACKGROUND: Isolated high-grade tears of the lateral collateral ligament (LCL) of the knee are rare, as most injuries are part of a broader pattern of damage to the posterolateral corner. Limited data exist in the literature about the ideal management of isolated LCL injuries, especially in elite-level athletes. HYPOTHESIS: Operative and nonoperative treatment of MRI-documented isolated grade III LCL injury can produce equal results in terms of return to play in the National Football League (NFL). STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: The NFL Injury Surveillance System was used to identify all players with lateral ligament injuries of the knee from 1994 to 2004. In addition, the medical staffs of all NFL clubs were surveyed about injuries during the same period. Nine players with MRI-documented isolated grade III LCL injuries were identified through this process. The medical staff for each respective player then completed a data questionnaire. Statistics were analyzed using 1-way analysis of variance. RESULTS: Four players underwent direct surgical repair of their injuries; they missed an average of 14.5 weeks of play and did not return within the same season. Five players were managed nonoperatively and missed an average of 2.0 weeks (P = .0001). Four of the 5 players in the nonoperative group returned within the same season at an average of 10 days; 1 missed the rest of the season. All 9 players were able to return to play the following season, and played for an average total of 2.8 (operative) and 4.4 (nonoperative) additional seasons (P = .253). CONCLUSION: Nonoperative management of MRI-documented isolated grade III lateral collateral ligament injuries in NFL athletes results in more rapid return to play without subjecting the player to the risks of surgery, while achieving an equal likelihood of return to play at the professional level.

Success of nonoperative management of adductor longus tendon ruptures in National Football League athletes.

BACKGROUND: Acute complete ruptures of the proximal adductor longus tendon are rare but challenging injuries to treat. The limited literature supports operative treatment, but data from management of chronic groin pain in athletes indicate that anatomical attachment of the tendon to the pubis may not be required for high-level function. HYPOTHESIS: Nonoperative management of complete adductor rupture can provide equal results to surgical repair in terms of return to play in the National Football League. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Using the National Football League Injury Surveillance System, adductor tendon ruptures documented by magnetic resonance imaging were identified in 19 National Football League players from 1992 to 2004. The team physician for each respective player completed a survey with information about history, physical examination, magnetic resonance imaging findings, treatment, and outcomes. Statistics were analyzed with a Student unpaired t test. RESULTS: Fourteen players were treated nonoperatively, and 5 players were treated with surgical repair using suture anchors. In both groups, all players eventually returned to play in the National Football League. Mean time for return to play was 6.1 +/- 3.1 weeks (range, 3-12 weeks) for the nonoperative group and 12.0 +/- 2.5 weeks (range, 10-16 weeks) for the operative group (P = .001). One player in the operative group suffered the complication of a draining wound and heterotopic ossification. Players represented a variety of positions, and 12 of 19 (63%) had experienced prior symptoms or events. CONCLUSION: Nonoperative treatment of proximal adductor tendon rupture results in a statistically significantly faster return to play than does operative treatment in athletes competing in the National Football League and avoids the risks associated with surgery while providing an equal likelihood of return to play at the professional level.

The effect of postoperative immobilization on the healing of radiofrequency heat probe modified tissue: assessment of tissue length, stiffness, and morphology.

The effect of postoperative immobilization on the length, stiffness, and structure of connective tissue after radiofrequency probe shrinkage was examined in a rabbit patellar tendon model. Tendon lengths were measured before, immediately following, and 2, 4, and 8 weeks following heat application, with the contralateral tendon as a control. The animals were randomly assigned to three groups. In Group I, the controls, the animals were allowed free caged activity for 8 weeks. In Groups II and III, the experimental limb was immobilized at 15 degrees of knee flexion for 2 and 4 weeks, respectively, after which the animals were allowed 6 and 4 weeks of free caged activity. Changes in tendon length, stiffness, and cross-sectional area were compared using repeated measures ANOVA and differences between groups examined using Tukey's post-hoc analysis. Patellar tendon lengths were increased in all 3 groups at 8 weeks (P< .001). Tissue elongation was less extensive in group III compared to group I at 8 weeks (P< .001), while tissue cross-sectional area was decreased in both groups II and III compared to group I at 8 weeks (P< .001). All groups demonstrated decreases in tensile strength when compared to controls (P< .001). These findings suggest that postoperative immobilization is important following thermal shrinkage of connective tissue, as early activity can lead to stretching of the heat-modified tissue.

An in vivo comparison of the modified Mason-Allen suture technique versus an inclined horizontal mattress suture technique with regard to tendon-to-bone healing: a biomechanical and histologic study in sheep.

The purpose of this study is to examine long-term tendon-to-bone healing, by use of a sheep animal model, after rotator cuff repairs performed with 2 different suture techniques: an inclined horizontal mattress suture pattern placed with special arthroscopic instrumentation (HMS) and the modified Mason-Allen pattern (MMA). After a pre hoc power analysis, 18 skeletally mature sheep were randomly assigned to either the HMS or MMA repair technique, with contralateral limbs used for the control group. At 26 weeks, the animals were euthanized. Six sheep from each group underwent biomechanical testing. Load-to-failure and stiffness results indicated no statistically significant difference between the 2 groups. Avulsion of the tuberosity was the primary mode of failure for both groups. In the remaining 6 sheep, histologic evaluation demonstrated that, regardless of treatment, the tendon appeared completely healed in the bony trough. Because the long-term biomechanical and histologic properties of healed tendons repaired with an HMA technique are equal to those obtained with an MMA technique, the inclined horizontal mattress suture may be appropriate for arthroscopic rotator cuff repair. Short-term studies are necessary to determine whether these findings are true early after tendon repair, when failure may be most common.

The effects of augmentation with Swine small intestine submucosa on tendon healing under tension: histologic and mechanical evaluations in sheep.

BACKGROUND: Rotator cuff failure after surgery may be attributed to inferior tissue healing properties that result from repetitive cyclic loading during early rehabilitation. Enhancing the biological healing process may reduce the incidence of failures after rotator cuff repairs. HYPOTHESIS: Augmentation of rotator cuff tissue using swine small intestine submucosa in a sheep model will improve the rate and quality of tissue repair. STUDY DESIGN: Controlled laboratory study. METHODS: We resected and reattached 26 sheep infraspinatus tendons under tension, with 13 animals receiving a small intestine submucosa patch (augmented group). Animals were sacrificed at 12 weeks, and biomechanical testing and histologic evaluation were performed. Biomechanical testing was completed in 10 tendons from each group. Specimens were loaded to failure at a constant displacement to obtain the load deformation curve used to calculate load to failure and stiffness of the healed bone-tendon interface. Histologic testing addressed tissue healing at the bone-tendon interface. RESULTS: The load-to-failure data did not indicate a significant difference between the augmented and nonaugmented groups (1252 +/- 402 N vs 985 +/- 459 N, respectively; P > .05). However, the augmented group had significantly better stiffness than the nonaugmented group (215 +/- 44 N/mm vs 154 +/- 63 N/mm, respectively; P = .03). Histologic data revealed that the infraspinatus tendon in all specimens inserted into the bone through a zone of fibrocartilage, although none of the patches were intact. CONCLUSION: Although there were no differences in the load-to-failure data between the 2 groups, the statistically significant improvement in stiffness for the augmented group is clinically relevant. Stiffness is the biomechanical parameter representing the tissue response to subdestructive loads seen with early rehabilitation. Augmenting the repair with a collagen matrix improved the early healing characteristics of the repair construct. CLINICAL RELEVANCE: Enhancing the biological process of tendon healing under tension by using a collagen matrix patch may improve the ultimate success of rotator cuff repair.

Incidence and location of bone bruises after acute posterior cruciate ligament injury.

BACKGROUND: In patients suffering from an anterior cruciate ligament injury, the incidence and location of bone bruises are well documented. This study reports data regarding bone bruises after acute posterior cruciate ligament injury. HYPOTHESIS: Bone bruises associated with posterior cruciate ligament injury are common, and their location differs from those seen with anterior cruciate ligament injury. STUDY DESIGN: Retrospective cohort study. METHODS: Thirty-five consecutive patients were identified as having a grade II or III posterior cruciate ligament tear, with an intact anterior cruciate ligament, in which a magnetic resonance imaging scan had been obtained within 20 days of injury. Magnetic resonance imaging scans were reviewed to document bone bruises, associated medial or lateral ligamentous injury, and meniscal and chondral abnormalities. RESULTS: Of the 35 patients, 29 (83%) had a bone bruise in at least one location. Bone bruises were found throughout the joint, more widely dispersed than is commonly seen with anterior cruciate ligament injury. Also, 29 patients had magnetic resonance imaging findings of associated ligamentous injury. Lateral bone bruises were associated with medial collateral ligament injury, whereas medial bone bruises correlated with posterolateral injury. CONCLUSIONS: The incidence of bone bruises associated with posterior cruciate ligament injury is similar to that seen with anterior cruciate ligament injury. Their location is more widely dispersed. The location of a bone bruise should lead to careful magnetic resonance imaging inspection and physical examination for ligamentous injury to the opposite side of the joint. Truly isolated posterior cruciate ligament injuries are rare, as most occur with osseous and some degree of associated ligamentous injury.