Increased utilization of constraint in total knee arthroplasty following anterior cruciate ligament and multiligament knee reconstruction.

AIMS: Anterior cruciate ligament (ACL) and multiligament knee (MLK) injuries increase the risk of development of knee osteoarthritis and eventual need for total knee arthroplasty (TKA). There are limited data regarding implant use and outcomes in these patients. The aim of this study was to compare the use of constrained implants and outcomes among patients undergoing TKA with a history of prior knee ligament reconstruction (PKLR) versus a matched cohort of patients undergoing TKA with no history of PKLR. PATIENTS AND METHODS: Patients with a history of ACL or MLK reconstruction who underwent TKA between 2007 and 2017 were identified in a single-institution registry. There were 223 patients who met inclusion criteria (188 ACL reconstruction patients, 35 MLK reconstruction patients). A matched cohort, also of 223 patients, was identified based on patient age, body mass index (BMI), sex, and year of surgery. There were 144 male patients and 79 female patients in both cohorts. Mean age at the time of TKA was 57.2 years (31 to 88). Mean BMI was 29.7 kg/m2 (19.5 to 55.7). RESULTS: There was a significantly higher use of constrained implants among patients with PKLR (76 of 223, 34.1%) compared with the control group (40 of 223, 17.9%; p < 0.001). Subgroup analysis showed a higher use of constrained implants among patients with prior MLK reconstruction (21 of 35, 60.0%) compared with ACL reconstruction (55 of 188, 29.3%; p < 0.001). Removal of hardware was performed in 69.5% of patients with PKLR. Mean operative time (p < 0.001) and tourniquet time (p < 0.001) were longer in patients with PKLR compared with controls. There were no significant differences in rates of deep vein thrombosis, pulmonary embolism, infection, transfusion, postoperative knee range of movement (ROM), or need for revision surgery. There was no significant difference in preoperative or postoperative Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS, JR) scores between groups. CONCLUSION: Results of this study suggest a history of PKLR results in increased use of constrained implants but no difference in postoperative knee ROM, patient-reported outcomes, or incidence of revision surgery. Cite this article: Bone Joint J 2019;101-B(7 Supple C):77-83.

Effect of pre-operative expectations on the outcomes following total shoulder arthroplasty.

AIMS: Few studies have evaluated the relationship between patients' pre-operative expectations and the outcome of orthopaedic procedures. Our aim was to determine the effect of expectations on the outcome after primary anatomical total shoulder arthroplasty (TSA). We hypothesised that patients with greater expectations would have better outcomes. PATIENTS AND METHODS: Patients undergoing primary anatomical TSA completed the Hospital for Special Surgery's Shoulder Expectations Survey pre-operatively. The American Shoulder and Elbow Surgeons (ASES), Shoulder Activity Scale (SAS), Short-Form-36 (SF-36), and visual analogue scale (VAS) for pain, fatigue, and general health scores were also collected pre-operatively and two years post-operatively. Pearson correlations were used to assess the relationship between the number of expectations and the outcomes. Differences in outcomes between those with higher and lower levels of expectations for each expectation were assessed by independent samples t-test. Multivariable linear regression analysis was used to control for potential confounding factors. RESULTS: A total of 67 patients were evaluated two years post-operatively. Most parameters of outcome improved significantly from baseline and most patients were satisfied. A greater number of expectations was associated with a significantly greater improvement in the ASES score (p = 0.02). In the multivariable analysis, a greater number of expectations was an independent predictor of better ASES, VAS and SF-36 scores, as well as improvements in ASES and VAS pain scores (p < 0.05). Greater expectations for many specific expectation questions were significantly associated with better outcomes (p < 0.05). CONCLUSION: TSA is a successful procedure with significant improvements in outcome, and greater pre-operative expectations are associated with better outcomes. Cite this article: Bone Joint J 2017;99-B:1190-6.

Preoperative planning for accurate glenoid component positioning in reverse shoulder arthroplasty.

BACKGROUND: Glenoid component positioning in reverse shoulder arthroplasty (RSA) is challenging. Patient-specific instrumentation (PSI) has been advocated to improve accuracy, and is based on precise preoperative planning. The purpose of this study was to determine the accuracy of glenoid component positioning when only the glenoid surface is visible, compared to when the entire scapula is visible on a 3D virtual model. METHODS: CT scans of 30 arthritic shoulders were reconstructed in 3D models. Two surgeons then virtually placed a glenosphere component in the model while visualizing only the glenoid surface, in order to simulate typical intraoperative exposure ("blind 3D" surgery). One surgeon then placed the component in an ideal position while visualizing the entire scapula ("visible 3D" surgery). These two positions were then compared, and the accuracy of glenoid component positioning was assessed in terms of correction of native glenoid version and tilt, and avoidance of glenoid vault perforation. RESULTS: Mean version and tilt after "blind 3D" surgery were +1.4° (SD 8.8°) and +7.6° (SD 6°), respectively; glenoid vault perforation occurred in 17 specimens. Mean version and tilt after "visible 3D" surgery were +0.3° (SD 0.8°) and +0.1° (SD 0.5°), respectively, with glenoid vault perforation in 6 cases. "Visible 3D" surgery provided significantly better accuracy than "blind 3D" surgery (P<0.05). CONCLUSION: When the entire scapula is used as reference, accuracy is improved and glenoid vault perforation is less frequent. This type of visualization is only possible with pre-operative 3D CT planning, and may be augmented by PSI. LEVEL OF EVIDENCE: Basic science study. Level III.

Anterior deltoid deficiency in reverse total shoulder replacement: a biomechanical study with cadavers.

Reverse total shoulder replacement (RTSR) depends on adequate deltoid function for a successful outcome. However, the anterior deltoid and/or axillary nerve may be damaged due to prior procedures or injury. The purpose of this study was to determine the compensatory muscle forces required for scapular plane elevation following RTSR when the anterior deltoid is deficient. The soft tissues were removed from six cadaver shoulders, except for tendon attachments. After implantation of the RTSR, the shoulders were mounted on a custom-made shoulder simulator to determine the mean force in each muscle required to achieve 30° and 60° of scapular plane elevation. Two conditions were tested: 1) Control with an absent supraspinatus and infraspinatus; and 2) Control with anterior deltoid deficiency. Anterior deltoid deficiency resulted in a mean increase of 195% in subscapularis force at 30° when compared with the control (p = 0.02). At 60°, the subscapularis force increased a mean of 82% (p < 0.001) and the middle deltoid force increased a mean of 26% (p = 0.04). Scapular plane elevation may still be possible following an RTSR in the setting of anterior deltoid deficiency. When the anterior deltoid is deficient, there is a compensatory increase in the force required by the subscapularis and middle deltoid. Attempts to preserve the subscapularis, if present, might maximise post-operative function.

In vivo healing after capsular plication in an ovine shoulder model.

Traditionally, arthroscopic management of shoulder instability has been reserved for patients with isolated Bankart lesions without any capsular laxity or injury. To date, there are no animal studies evaluating the healing potential of capsular plication and/or capsulo-labral repair. The purpose of this in vivo animal study was to determine if the histological capsular healing of an open capsular plication simulating an arthroscopic plication is equivalent to the more traditional open capsular shift involving cutting and advancing the capsule. Twenty-six skeletally mature sheep were randomized to either an open capsular plication simulating arthroscopic plication (n = 13), or an open traditional capsular shift (n = 13). A sham operation (n = 4) was also performed involving exposure to visualize the capsule. Normal non-operated control shoulders were also analyzed. A pathologist blinded to the treatment evaluated both hematoxylin and eosin (H&E) sections and polarized light microscopy. Qualitative scoring evaluated fibrosis, mucinous degeneration, fat necrosis, granuloma formation, vascularity, inflammatory infiltrate and hemosiderin (0 to 3 points). Both the capsular plication and open shift groups demonstrated healing by fibrosis at the site of surgical manipulation. There were no statistical differences in the capsular healing responses between the two groups with regard to fibrosis, granuloma formation and vascularity. The open shift group demonstrated significantly more mucinous degeneration (p = 0.038). Fat necrosis was present in 4/13 specimens in the open shift group and none in the capsular plication specimens. Both groups demonstrated disorganized collagen formation under polarized light microscopy. There were no differences between non-operated control specimens and sham surgery specimens. Our findings support the hypothesis that histologic capsular healing is equivalent between the plication group and the open shift group. In addition, the open shift group demonstrated significantly more changes indicative of tissue injury. This basic science model confirms capsular healing after simulated arthroscopic plication, providing support for arthroscopic capsular plication in practice.

Motion loss after ligament injuries to the knee. Part II: prevention and treatment.

This is the second part of a two-part review on motion problems after ligament injuries to the knee. The first part, published in the September/October 2001 issue, discussed normal and abnormal knee motion, terminology, risk factors, and pathoanatomy. The purpose of this article is to review current concepts on prevention and treatment of motion problems, summarizing the recent and pertinent studies that discuss this complicated clinical problem. The first part of this article will discuss the different classification schemes that have been published on motion loss of the knee. Prevention strategies will be discussed next, followed by early recognition. Finally, a discussion of the various treatment options and published results will be presented in detail, together with the authors' nine-step systematic surgical approach to the stiff knee.

Mucoid degeneration of the anterior cruciate ligament.

A case of intraligamentous mucoid degeneration of the anteromedial band of the anterior cruciate ligament (ACL) is presented. The patient had knee pain without clinical or diagnostic evidence of instability. Isolated debridement of the anteromedial band resulted in immediate pain relief with rapid return to athletic activities without instability. We present this case to demonstrate the presence of intraligamentous mucoid degeneration in the ACL as a source of knee pain without instability. Partial ACL debridement did not preclude adequate knee stability.

Correlation of radiographic and arthroscopic findings with rotator cuff tears and degenerative joint disease.

The purpose of this study was to identify early signs of rotator cuff tear and glenohumeral articular cartilage degeneration by using conventional radiography. A non-weighted anteroposterior oblique and a weighted active abduction view were evaluated for superior humeral migration and matching degenerative changes at the inferolateral acromion and superior aspect of the greater tuberosity in 40 patients who underwent shoulder arthroscopy. Measurements of the glenohumeral distance were performed. Surgical reports were reviewed to determine rotator cuff and glenohumeral articular cartilage status. Matching degenerative changes correlate with complete rotator cuff tear (P =.04); superior migration does not. Severe glenohumeral cartilage loss correlates with narrowing of the superior joint space on the anteroposterior oblique radiograph (P =.02) and with narrowing of the mid joint space on the active abduction view (P =.05). Both glenohumeral articular cartilage degenerative change and rotator cuff injury, before formation of typical sequelae of chronic rotator cuff tear, can be detected with the use of conventional radiography.

Reliability, validity, and responsiveness of four knee outcome scales for athletic patients.

BACKGROUND: Many patient-based knee-rating scales are available for the evaluation of athletic patients. However, there is little information on the measurement properties of these instruments and therefore no evidence to support the use of one questionnaire rather than another. The goal of the present study was to determine the reliability, validity, and responsiveness of four knee-rating scales commonly used for the evaluation of athletic patients: the Lysholm scale, the subjective components of the Cincinnati knee-rating system, the American Academy of Orthopaedic Surgeons sports knee-rating scale, and the Activities of Daily Living scale of the Knee Outcome Survey. METHODS: All patients in the study had a disorder of the knee and were active in sports (a Tegner score of 4 points). Forty-one patients who had a knee disorder that had stabilized and who were not receiving treatment were administered all four questionnaires at baseline and again at a mean of 5.2 days (range, two to fourteen days) later to test reliability. Forty-two patients were administered the scales at baseline and at a minimum of three months after treatment to test responsiveness. The responses of 133 patients at baseline were studied to test construct validity. RESULTS: The reliability was high for all scales, with the intraclass correlation coefficient ranging from 0.88 to 0.95. As for construct validity, the correlations among the knee scales ranged from 0.70 to 0.85 and those between the knee scales and the physical component scale of the Short Form-36 (SF-36) and the patient and clinician severity ratings ranged from 0.59 to 0.77. Responsiveness, measured with the standardized response mean, ranged from 0.8 for the Cincinnati knee-rating system to 1.1 for the Activities of Daily Living scale. CONCLUSIONS: All four scales satisfied our criteria for reliability, validity, and responsiveness, and all are acceptable for use in clinical research.

The accessory posterior portal for shoulder arthroscopy: Description of technique and cadaveric study.

As the indications for shoulder arthroscopy continue to expand, so too does the need for complete access to the glenohumeral joint. Specific regions of the joint, including the axillary recess, are often times difficult to access using traditionally described posterior and anterior portals. In this article, we describe a technique for the placement of an accessory posterior portal into the inferior hemisphere of the glenohumeral joint, effectively in the 8 o'clock or 4 o'clock position. To demonstrate the safety and effectiveness of this portal, 6 cadaveric specimens were dissected after the placement of a standard and accessory posterior portal. The proximity of the posterior portals to the axillary and suprascapular nerves was analyzed. Measurements were made in simulated beach-chair and lateral decubitus positions. The authors show that the accessory posterior portal is safe to use and may prove useful to the surgeon who wishes to gain access to the inferior recesses of the glenohumeral joint.

Arthroscopic treatment of coracoid impingement.

A review of the literature reveals that surgical treatment of coracoid impingement has heretofore involved open surgical decompression in all cases. Previously unreported, the authors describe an arthroscopic technique to treat coracoid impingement syndrome, demonstrate its feasibility, and cover the specific technical points that facilitate this procedure.

Extra-articular origin of biceps brachii.

We report a clinically relevant anatomic variation of the tendon of the long head of biceps brachii muscle. The clinical and historically relevant data regarding an anatomic finding observed in 1 patient are reviewed. The clinical outcome of the patient's care was successful. Recognition of the described anatomic variant of the biceps tendon can aid the surgeon in focusing the treatment on the actual pathology and not on aberrant anatomy. Several anatomic variations in the origin of the long head of the biceps brachii have been observed. Some of these anomalies have been implicated as having a role in rotator cuff tendinopathy or in exposure for shoulder surgery. We are reporting the observation that the long head of the biceps tendon may have a mesotendon or be incorporated in the extra-articular side of the glenohumeral joint capsule, making arthroscopic visualization and assessment of the tendon difficult.

Arthroscopic bankart repair: experience with an absorbable, transfixing implant.

The use of arthroscopic means to address shoulder instability has provided a technically advantageous way to approach Bankart lesions while posing complex questions regarding the specific indications for such an intervention. A successful outcome with arthroscopic Bankart repair is a function of proper surgical indication and patient selection. Several authors have evaluated the causes of failure and reasons for success with the Suretac device. The development of a bioabsorbable repair device at the authors' institution was precipitated by a desire to address and repair Bankart lesions arthroscopically while avoiding the frequent complications associated with the metal staple and the transglenoid suture technique. The Suretac represents the first generation of bioabsorbable transfixing devices. The initial objectives of the Suretac device were to adequately and dynamically tension soft tissue to bone, while providing a bioabsorption profile that mirrored the native healing response. The Suretac device is an appropriate surgical tool for arthroscopically repairing Bankart lesions in a carefully selected patient population.

Enhanced matrix synthesis and in vitro formation of cartilage-like tissue by genetically modified chondrocytes expressing BMP-7.

Bone morphogenic protein-7 (BMP-7) supports ectopic cartilage and bone formation, is expressed in normal articular cartilage, and increases matrix synthesis in chondrocytes. Based on this knowledge, we hypothesized that an adenovirus (Ad) vector encoding human BMP-7 could be used to modify chondrocytes genetically to improve their capacity for cartilage repair. An adenovirus vector encoding BMP-7 (AdBMP-7) was constructed and its bioactivity confirmed by ectopic bone formation assay. AdBMP-7 modification of bovine chondrocytes induced expression of BMP-7 mRNA and bioactive protein, resulting in an increase in incorporation of 35SO4- into proteoglycan, 3H-proline uptake into protein, and the expression of the cartilage-specific matrix genes, aggrecan and type II collagen. An in vitro model of chondrocyte transplantation was used to demonstrate the feasibility of using genetically modified chondrocytes to enhance formation of cartilage-like tissue. When transplanted onto cartilage explants and maintained in vitro for 3 weeks, chondrocytes modified with AdBMP-7 formed 1.9-fold thicker tissue than chondrocytes modified with a control vector (P < 0.001). This tissue was positive for type II collagen and proteoglycan but negative for type X collagen and demonstrated a cartilage-like morphology. These observations suggest that Ad-mediated transfer of BMP-7 gene to chondrocytes enhances the chondrocyte-specific matrix synthesis and their capacity to form cartilage-like tissue, thus representing a strategy that may improve cell-based cartilage repair.

Motion loss after ligament injuries to the knee. Part I: causes.

Motion loss continues to be a difficult complication after ligament injury and surgery to the knee. A better understanding of the pathoanatomic causes of motion loss can lead to improved prevention and treatment strategies. When motion loss does occur, early recognition and appropriate treatment can be expected to restore motion and improve function in most patients. Treatment options, although varied, should improve outcome when implemented appropriately. This article is composed of two parts. The first part reviews the current concepts on definitions, incidence, and causes of motion loss. In the second part, to be published later, current strategies on prevention and treatment of motion loss after ligament injury to the knee are reviewed. Emphasis is placed on risk factors and prevention as well as on diagnosis and treatment. The article summarizes the latest information from the basic sciences as well as clinical studies on the problem of motion loss of the knee and attempts to provide a rational approach to these difficult clinical problems.

Patients' expectations of knee surgery.

BACKGROUND: Patients' expectations of medical care are linked to their requests for treatment and to their assessments of outcome and satisfaction. Our goals were to measure patients" preoperative expectations of knee surgery and to develop and test patient-derived knee expectations surveys. METHODS: An initial sample of 377 patients (mean age, 54.6 18.2 years; 52% women) was enrolled in the survey-development phase. One hundred and sixty-one (43%) of these patients subsequently underwent total knee arthroplasty; seventy-five (20%), cruciate ligament repair; eighty-five (23%), meniscal surgery; and fifty-six (15%), surgery for another knee condition. Preoperatively, these patients were asked open-ended questions about their expectations of knee surgery. Their responses were grouped with use of qualitative research techniques to generate categories of expectations. Categories were transformed into specific questions and were formatted into two draft surveys, one for patients undergoing total knee arthroplasty and one for patients undergoing other surgical procedures on the knee. A second sample of 163 patients (mean age, 55.1 17.5 years; 49% women) was enrolled in the survey-testing phase, and they completed the draft surveys on two separate occasions to establish test-retest reliability. Items were selected for the final surveys if they were cited by 5% of the patients, if they represented important functional changes resulting from surgery, or if they represented potentially unrealistic expectations. All selected items fulfilled reliability criteria, defined as a kappa (or weighted kappa) value of 0.4, or were deemed to be clinically relevant by a panel of orthopaedic surgeons. RESULTS: From the survey-development phase, a total of fifty-two categories of expectations were discerned; they included both anticipated items such as pain relief and improvement in walking ability and unanticipated items such as improving psychological well-being. Expectations varied by diagnosis and patient characteristics, including functional status. Two final surveys were generated: the seventeen-item Hospital for Special Surgery Knee Replacement Expectations Survey and the twenty-item Hospital for Special Surgery Knee Surgery Expectations Survey. Each required less than five minutes to complete. CONCLUSIONS: Patients have multiple expectations of knee surgery in the areas of symptom relief and improvement of physical and psychosocial function, and these expectations vary according to the diagnosis. We developed two valid and reliable surveys that can be used preoperatively to direct patient education and shared decision-making and to provide a framework for setting reasonable goals. Reexamining patients' responses postoperatively could provide a way to assess fulfillment of expectations, which is a crucial patient-derived measure of outcome and satisfaction.

Complications of thermal capsulorrhaphy.

As the popularity of thermal capsular shrinkage continues to increase, analysis of complications and failures will continue to provide helpful information in guiding patient selection and decreasing morbidity. Patients who are undergoing revision surgery or who have a history of multiple preoperative dislocations appear to be at higher risk for failure with thermal shrinkage surgery. Caution should be exercised for patients who participate in contact or collision sports, as well as those with MDI. Further study may determine whether thermal shrinkage is most appropriate for microinstability or used as an adjunct to other stabilization procedures.

The effect of cytokines on the migration of fibroblasts derived from different regions of the canine shoulder capsule.

This study examined the effect of several cytokines on the chemotactic migration of fibroblasts derived from 3 different parts of the canine shoulder: the upper part of the medial glenohumeral ligament (equivalent to the anterior part of the inferior glenohumeral ligament of the human shoulder); the inferior part of the medial glenohumeral ligament (equivalent to the axillary pouch of the human shoulder); and the posterior capsule (equivalent to the thin posterior capsule in the human shoulder). Platelet-derived growth factor-AB stimulated the migration of all 3 cell types in a dose-dependent manner, with increases from 150% to 300% at 1 ng/mL to 500% to 700% at 10 ng/mL. Hepatocyte growth factor also stimulated the migration of all 3 cell types in a dose-dependent manner (130% to 310%). Insulinlike growth factor-1 increased the migration of all 3 types of fibroblasts by 160% to 250%. Bone morphogenic protein-2, interleukin-1, and transforming growth factor-b had no significant effect on migration of shoulder capsular fibroblasts. These data demonstrate that capsular fibroblasts are responsive to specific growth factors and suggest the potential for use of growth factors to augment healing and/or remodeling of the shoulder capsule.