A Patella-Sided Tensioning Technique for Medial Patellofemoral Ligament Reconstruction.

Reconstruction of the medial patellofemoral ligament (MPFL) is a common procedure for treatment of recurrent patellofemoral instability. Over the last two decades, multiple surgical techniques for MPFL reconstruction have been described with no clear consensus on a superior reconstruction technique. Appropriate graft tensioning is one of the most important factors for a successful MPFL reconstruction. Overtensioning of the MPFL graft can lead to patellofemoral joint overload and undertensioning can lead to recurrent instability. Current literature demonstrates descriptions of MPFL reconstruction with final graft tensioning performed off of the femoral side. We describe a technique in this article for performing final graft tensioning from the patellar side, which gives the surgeon an option for intraoperative tension adjustments after evaluating patellar tracking.

The State of Meniscal Allograft Transplantation in New York Over the Last Decade.

BACKGROUND: The purpose of this study was to evaluate for changes in the incidence of arthroscopic meniscal procedures, especially meniscal allograft transplantation (MAT) in New York State (NYS) between 2005 to 2014. METHODS: The New York Statewide Planning and Research Cooperative Systems (SPARCS) database was queried from 2005 through 2014 to identify patients undergoing meniscetomies, meniscal repairs, and MAT. Patients were followed longitudinally to determine the incidence of subsequent ipsilateral knee procedures. The impact of patient demographics and surgeon volume on reoperation was explored. RESULTS: From 2005 through 2014, there were 524,737 arthroscopic meniscal procedures. Of these, there were 510,406 meniscectomies, 14,214 meniscal repairs, and 117 MATs. The number of MATs increased 15.5% per year, with the largest increase being between 2013 to 2014 (an increase of 86.5%). Average MAT patient age was 29.8 ± 11.1 years; 65.0% of patients were male; 66% were Caucasian; 84% were privately-insured; and 23% of surgeons met the criteria for high-volume (five or more MATs in a year). A total of 25.6% (30/117) patients underwent subsequent surgery; 26 patients underwent knee procedures at mean of 18.9 ± 18.3 months after initial MAT, the most common of which were ipsilateral meniscectomies (19/26). Four patients underwent total knee arthroplasty (TKA) at a mean of 21.0 ± 9.2 months after initial MAT. Patients undergoing TKA after MAT were significantly older (42.0 ± 15.0 years vs, 29.3 ± 10.7 years; p = 0.0242) than patients who did not. Neither demographics nor surgeon volume were statistically significant factors for undergoing subsequent surgery (p > 0.05). CONCLUSION: Meniscal allograft transplantation, though relatively uncommon, is being performed with greater frequency in NYS. Surgeons should counsel patients regarding the likelihood of requiring subsequent knee surgery after MAT, with repeat arthroscopic partial meniscectomy being the most commonly performed procedure.

A novel intraoperative method to project osteotomy lines for accurate resection of primary bone sarcomas.

Background: Accurate reproduction of a preoperative plan is critical in wide resection of bone sarcomas. Recent advances in computer navigation and 3D-custom jigs have increased resection accuracy, although with certain practical drawbacks. Methods: We developed a novel "projector method" that projects the preoperative osteotomy lines onto the bone. A sawbone study was conducted to evaluate accuracy in reproducing preoperative resection plans. An additional cadaver experiment was conducted to evaluate feasibility in a more realistic operating room setting. Results: Based on the results of experiments conducted on sawbones, the proposed light projector method was more accurate at depicting desired osteotomy lines than a traditional manual method, reducing the corner deviation from 2.53 mm to 0.35 mm, angular deviation from 2.10° to 0.31°, and point deviation from 4.66 mm to 0.48 mm (p < 0.001). Results of the cadaver experiment were consistent with those of sawbone experiments. Conclusions: The new projector method can accurately assist surgeons in visualizing the preoperative plan of osteotomy lines accurately in surgery.

A Novel 3D Light Assisted Drawing (3D-LAD) Method to Aid Intraoperative Reproduction of Osteotomy Lines Surrounding a Bone Tumor During Wide Resection: An Experimental Study.

Introduction: Computer navigation and customized 3D-printed jigs improve accuracy during bone tumor resection, but such technologies can be bulky, costly, and require intraoperative radiation, or long lead time to be ready in OR. Methods: We developed a method utilizing a compact, inexpensive, non-X-ray based 3D surface light scanner to provide a visual aid that helps surgeons accurately draw osteotomy lines on the surface of exposed bone to reproduce a well-defined preoperative bone resection plan. We tested the accuracy of the method on 18 sawbones using a distal femur hemimetaphyseal resection model and compared it with a traditional, freehand method. Results: The method significantly reduces the positional error from 2.53 (±1.13) mm to 1.04 (±0.43) mm (p<0.001), and angular error of the front angle from 2.10° (±0.83°) to 0.80° (±0.66°) (p=0.001). The method also reduces the mean maximum deviation of the bone resection, with respect to the preoperative path, from 3.75mm to 2.69mm (p=0.003). However, no increased accuracy was observed at the back side of the bone surface where this method would not be expected to provide information. Discussion: In summary, we developed a novel 3D-LAD navigation technology. From the experimental study, we demonstrated that the method can improve the ability of surgeons to accurately draw the preoperative osteotomy lines and perform resection of a primary bone sarcoma, with comparison to traditional methods, using 18 sawbones.

A novel method of light projection and modular jigs to improve accuracy in bone sarcoma resection.

We developed a novel method using a combined light-registration/light-projection system along with an off-the-shelf, instant-assembly modular jig construct that could help surgeons improve bone resection accuracy during sarcoma surgery without many of the associated drawbacks of 3D printed custom jigs or computer navigation. In the novel method, the surgeon uses a light projection system to precisely align the assembled modular jig construct on the bone. In a distal femur resection model, 36 sawbones were evenly divided into 3 groups: manual-resection (MR), conventional 3D-printed custom jig resection (3DCJ), and the novel projector/modular jig (PMJ) resection. In addition to sawbones, a single cadaver experiment was also conducted to confirm feasibility of the PMJ method in a realistic operative setting. The PMJ method improved resection accuracy when compared to MR and 3DCJ, respectively: 0.98 mm versus 7.48 mm (p < 0.001) and 3.72 mm (p < 0.001) in mean corner position error; 1.66 mm versus 9.70 mm (p < 0.001) and 4.32 mm (p = 0.060) in mean maximum deviation error; 0.79°-4.78° (p < 0.001) and 1.26° (p > 0.999) in mean depth angle error. The PMJ method reduced the mean front angle error from 1.72° to 1.07° (p = 0.507) when compared to MR but was slightly worse compared to 0.61° (p = 0.013) in 3DCJ. The PMJ method never showed an error greater than 3 mm, while the maximum error of other two control groups were almost 14 mm. Similar accuracy was found with the PMJ method on the cadaver. A novel method using a light projector with modular jigs can achieve high levels of bone resection accuracy, but without many of the associated drawbacks of 3D printed jigs or computer navigation technology.

A novel bone registration method using impression molding and structured-light 3D scanning technology.

Accurate bone registration is critical for computer navigation and robotic surgery. Existing registration systems are expensive, cumbersome, limited in accuracy and/or require intraoperative radiation. We recently reported a novel method of registration utilizing an inexpensive, compact, and X-ray-free structured-light 3D scanner. However, this technique is not always practical in a real surgical setting where soft tissue and blood can obstruct the continuous line-of-sight required for structured-light technology. We sought to remedy these limitations using a novel technique using rapid-setting impression molding to capture bone surface features and scan the undersurface of the mold with a structured-light scanner. The photonegative of this mold is compared to the preoperative computed tomography (CT)-scan to register the bone. A registration accuracy study was conducted on 36 CT-scanned femur sawbones, simulating typical exposure in hip/knee arthroplasty and bone tumor surgery. A cadaver experiment was also conducted to evaluate the feasibility of using the impression molding in a more realistic operating room setting. The registration accuracy of the proposed technique was 0.50 ± 0.19 mm. This was close to the reported accuracy of 0.43 ± 0.18 mm using a structured-light scanner without impression molding (p = 0.085). In comparison, historical values for "paired-point" and intraoperative CT image-based registration methods currently used in modern robotic/computer-navigation systems were 0.68 ± 0.14 mm (p = 0.004) and 0.86 ± 0.38 mm, respectively. The registration accuracy of the cadaver experiment was consistent with that of sawbone experiments. Although future studies are needed to extend to human subjects, this study shows that the impression molding method can produce comparable or better registration accuracy than the existing techniques.

Collagen-Based Bioinductive Implant for Treatment of Partial Thickness Rotator Cuff Tears.

INTRODUCTION: Partial thicknessrotator cuff tears(PTRCT) have low healing potential and tend to progress over time if not addressed surgically. There is a relative paucity of literature discussing optimal treatment for symptomatic PTRCT as compared to full thicknessrotator cuff tears. The available data supports a treatment course of debridement with or without acromioplasty for symptomatic patients with tears less than 50% in thickness combined with the use of repair (conversion to full thickness or transtendinous) for symptomatic patients with tears greater than 50% in thickness. The aim of this study was to evaluate functional and radiographic outcomes following surgical implantation of a collagen-based bioinductive implant for PTRCT. METHODS: Patients with PTRCT who underwent implantation of a collagen-based bioinductive implant over the bursal surface of the rotator cuff were identified. Patients who had an implant placed to augment a standard full thickness repair were excluded from analysis. We administered questionnaires to patients with a minimum of 6 months since surgery and collected patient data including demographics, preoperative and postoperative American Shoulder and Elbow Society (ASES) scores, preoperative and postoperative visual analog scale (VAS) pain scores, complications, and satisfaction level. Magnetic resonance imaging (MRI) was obtained as needed, at 6 months, or at 12 months postoperatively, and tendon thickness was measured on coronal views. RESULTS: Thirty patients were identified who met the inclusion and exclusion criteria. Twenty-four patients (80% response rate) were available for follow-up; 19 were male and five were female. Mean age and body mass index were 54.5 ± 11.6 years and 28.6 ± 5.9 kg/m2 , respectively. Mean tear thickness as measured intraoperatively was 56.6%. There were 16 (66.7%) articular-sided, five (20.8%) bursal-sided, and three (12.5%) intrasubstance tears. Mean survey follow-up time was 19.1 months. Mean ASES scores increased significantly from 45.6 preoperatively to 68.1 postoperatively (p = 0.001). Mean VAS pain scores decreased significantly from 8.3 preoperatively to 3.8 postoperatively (p < 0.001). Mean patient satisfaction level was 7.5. Ten patients had both a preoperative and postoperative MRI available for comparison. Tendon thickness at the tear site increased significantly from 5.7 mm preoperatively to 6.5 mm at mean 9.9 months follow-up (p = 0.007). There were no implant-related complications. One patient suffered a traumatic re-tear 4 months postoperatively. CONCLUSION: Highly porous collagen-based bioinductive implants are safe and effective forreducing pain and improving shoulderfunction in patientswith PTRCT of approximately 50%, with radiographic evidence of new tissue formation. Randomized controlled trials are needed to assess efficacy relative to debridement and standard repair techniques.

Open Surgical Management of Chronic Exertional Compartment Syndrome of the Leg.

PURPOSE: The purpose of this study is to present one institution's experience managing chronic exertional compartment syndrome (CECS) and to identify patient and surgical characteristics associated with better outcomes following open surgical management of CECS with specific emphasis on return to sports. METHODS: Fifteen patients (10 male, 5 female) who underwent open fasciotomy for CECS with a minimum of 1-year follow-up were included. Chart review was performed to obtain patient demographics, medical and surgical history, presenting symptomatology, and surgical details of fasciotomy. Outcomes were assessed using follow-up questionnaires that consisted of Tegner Activity Scale, EuroQol-5D (EQ5D) index score, EQ-5D rating scale, symptom resolution, patient satisfaction, and return to sports. RESULTS: The mean patient age at the time of surgery was 28.1 years (range: 17 to 49 years). At mean follow-up of 2.7 years (range: 1.0 to 5.1 years), five patients reported complete resolution of symptoms, eight reported improvement (but not resolution) of symptoms, one reported no change in symptoms, and one reported worsening of symptoms. The mean Tegner Activity Score was 6.7 (range: 1 to 9) prior to injury and 4.7 (range: 1 to 9) postoperatively. Patients with any preoperative symptoms at rest had significantly lower Tegner before score (4.0 vs. 7.1, p = 0.036) and EQ5D rating (50.0 vs. 83.5, p = 0.04) compared to those that only experienced symptoms with activity. Patients that had prior surgery, including fasciotomy, had significantly lower EQ-5D rating than patients with no history of prior lower extremity surgery (56.7 vs. 84.6, p = 0.045). Although 10 (66%) patients were able to return to sports, only four (27%) of them were able to return to their prior level of sport. The overall satisfaction rate was 87%. CONCLUSION: Although open surgical fasciotomy for treatment of chronic exertional compartment syndrome leads to high rates of symptom improvement or resolution, fewer patients are able to return to their prior level of sports. Presence of symptoms at rest, presence of bilateral symptoms, and history of prior lower extremity surgery all portend worse outcomes.

Clinical Outcomes after Mini-Open Excision of Popliteal Cysts.

PURPOSE: The purpose of the study was to investigate clinical outcomes following a mini-open posterior technique. METHODS: Patients who received mini-open popliteal cyst excisions between April 1999 and April 2010 were identified. Charts were retrospectively reviewed for postoperative complications, cyst recurrence, previous aspiration, re-operation, intraoperative findings, cyst size, comorbidities, and co-surgeries. Visual Analogue Pain Scale and Rauschning's symptomatic knee criteria were collected prospectively to assess functional outcomes. RESULTS: Twenty-two legs in 21 patients were included in the study [males: 12 (57%); females: 9 (43%); age: 48.23 ± 11.74 years; BMI: 26.7 ± 4.54 kg/m2; follow-up: 4.55 ± 3.01 years]. Average cyst size was 4.16 ± 1.64 cm and were all located in the posteromedial aspect of the leg. All 22 cases had associated intra-articular pathology based on MRI, physical examination, and arthroscopy. Complications after cyst excision included: paresthesia in the distribution of the saphenous nerve (3/22, 14%), keloid formation (1/22, 4%), joint effusion requiring aspiration (1/22, 4%), and one recurrence requiring cystectomy 10 years later (4%). All incidences of paresthesia resolved. Mean visual analog pain score decreased by 6 points (p < 0.001) and Rauschning and Lindgren score decreased by two categories, from a 2.6 (category 2-3) preoperatively to 0.6 (category 0-1) postoperatively (p < 0.001). CONCLUSION: Mini-open popliteal cyst excision is a safe and effective technique for refractory popliteal cysts in patients who desire a decrease in pain, an increase range of motion, and improved function in knee flexion and extension. Further studies are needed to evaluate the clinical outcomes of patients over a longer duration as our one patient with a 10-year follow-up required a repeat procedure.

Adipose-to-muscle area ratio at the knee is superior to BMI in predicting post-operative outcome following arthroscopic meniscectomy.

PURPOSE: To determine if measurement of leg adipose tissue area by MRI is a better predictor of post-operative clinical outcome compared to body mass index (BMI) following arthroscopic meniscectomy. METHODS: Patients that underwent an arthroscopic partial meniscectomy between 2011 and 2016 were identified and a retrospective chart review was performed. Patients with additional knee pathology other than a meniscal tear with or without associated articular cartilage injury were excluded. Leg adipose tissue and muscle area measurements at the level of the knee joint were performed for patients on their preoperative axial magnetic resonance imaging (MRI) study and adipose-to-muscle area ratio (AMR) was calculated. Correlations among AMR, BMI, and post-operative clinical outcomes were compared. RESULTS: A total of 74 patients (32 females and 42 males) were included (mean age 50.0 years, std. dev. 12.3 years). 35 patients underwent a partial medial meniscectomy, 15 underwent a partial lateral meniscectomy, and 24 underwent both. Linear regression analysis showed that the AMR, compared to BMI, had a significantly stronger correlation to both mean post-operative Knee Injury and Osteoarthritis Outcome Score (KOOS) across all 5 subscales (KOOS5) and Tegner Current score. Patients that had cartilage damage and concurrent chondroplasty tended to be older and have lower post-operative KOOS5 compared to those with no cartilage damage. AMR was also significantly correlated to age and BMI. CONCLUSIONS: The current study demonstrates that compared to BMI, leg adiposity as determined by the ratio of adipose tissue to muscle area on axial MRI (AMR), is a stronger predictor of functional outcome following meniscectomy. This suggests a role of obesity in the progression of OA beyond the increased joint forces associated with increased BMI. LEVEL OF EVIDENCE: IV, retrospective case series.

S1 Pedicle Subtraction Osteotomy for Fixed Sagittal Imbalance and Lumbosacral Kyphosis.

S1 pedicle subtraction osteotomies (PSOs) are indicated in patients with fixed, high-grade L5-S1 spondylolisthesis or kyphosis secondary to a sacral fracture, who present with severe sagittal imbalance. Unlike lumbar PSOs, sacral osteotomies are rare, and there is a paucity of literature outlining techniques. Here, we present the indications, planning, technique, and outcomes for S1 PSOs.

Posttraumatic Heterotopic Ossification of the Hip.

INTRODUCTION: Posttraumatic heterotopic ossification (HO) of the hip frequently follows acetabular fracture and hip surgery and can become symptomatic, with significant pain and limited range of motion (ROM). Definitive treatment may require surgical excision, which can result in serious complications if not planned and executed appropriately. METHODS: Surgical excision of posttraumatic hip HO requires appropriate indications, preoperative planning, and intraoperative guidance using fluoroscopy to maximize excision of HO and minimize complications. This video presents a case of severe posttraumatic hip HO, indications and technique of surgical excision using fluoroscopic guidance, postoperative protocol, and the patient's clinical follow-up. RESULTS: Surgical excision along with appropriate postoperative HO prophylaxis and immediate mobilization resulted in significant improvement in hip ROM and return to activities of daily living without complications or recurrence. Intraoperative blood loss can be significant and should be appropriately planned for preoperatively. CONCLUSIONS: Posttraumatic hip HO can cause significantly limited hip ROM and pain with resulting disability. Surgical excision of posttraumatic hip HO in a preserved hip joint can be successful in restoring hip ROM and function. Appropriate postoperative HO prophylaxis can prevent recurrence.

Acute pulmonary embolism after arthroscopic glenoid labral repair and subacromial decompression: case report and review of the literature.

This report describes the case of a 29 year-old female with a history of polycystic ovary syndrome (PCOS) and on combined oral contraceptives who presents with an acute, CT confirmed pulmonary embolus of the right lower lobe, one week following arthroscopic labral repair of the right shoulder. This patient's relevant risk factors including obesity, oral contraceptive use, PCOS, and surgical positioning are discussed. Literature surrounding venous thromboembolism (VTE) following shoulder arthroscopy is also reviewed.

Excision of Os Trigonum in Dancers via an Open Posteromedial Approach.

An os trigonum is a potential source of posterior ankle pain in dancers, often associated with flexor hallucis longus (FHL) pathology. Surgical excision is indicated on failure of nonoperative management. Options for surgical excision include open excision (via a posterolateral or posteromedial approach), subtalar arthroscopy, and posterior endoscopy. Os trigonum excision via an open posteromedial approach with concomitant FHL tenolysis/tenosynovectomy is a safe and effective method for the operative treatment of a symptomatic os trigonum that allows for identification and treatment of associated FHL pathology. The major steps in the procedure, which are demonstrated in this video article, are: (1) preoperative planning with appropriate imaging; (2) patient is positioned in a supine position with the operative extremity in figure-of-4 position; (3) a 3-cm, slightly curvilinear longitudinal incision is made midway between the posterior aspect of the medial malleolus and the anterior aspect of the Achilles tendon, over the palpated FHL tendon, and the flexor retinaculum is exposed and incised; the neurovascular bundle is retracted anteriorly, exposing the FHL tendon and sheath; (4) FHL tenolysis/tenosynovectomy is performed; (5) the FHL is retracted anteriorly and a capsulotomy is performed over the os trigonum and the os trigonum is excised; (6) the capsule is repaired and closure is performed; and (7) dressings and a CAM (controlled ankle motion) walking boot are applied. The patient begins physical therapy at 2 weeks postoperatively and may return to dance at 4 to 6 weeks postoperatively as tolerated. In our series of 40 cases, 95% of patients who desired to return to dance were able to return to their pre-injury level of dance. There were no major neurovascular complications.

Bone Trough Lateral Meniscal Allograft Transplantation: The Tapered Teardrop Technique.

The meniscus plays a vital role in knee biomechanics, and its physical absence or functional incompetence (e.g., irreparable root or radial tear) leads to unacceptably high rates of joint degeneration in affected populations. Meniscal allograft transplantation has been used successfully to treat patients with postmeniscectomy syndrome, and there is early laboratory and radiographic evidence hinting at a potential prophylactic role in preventing joint degeneration. We present a technique for lateral meniscal allograft transplantation using the CONMED Meniscal Allograft Transplantation system.

Arthroscopic Repair of Hip Labrum With Suture Anchors.

The acetabular labrum and the transverse acetabular ligament form a continuous ring of tissue on the periphery of the acetabulum that provides a seal for the hip joint and increases the surface area to spread load distribution during weight-bearing. When a labral tear is suspected, the treatment algorithm always begins with conservative management, including physical therapy and nonsteroidal anti-inflammatory drugs. When conservative management fails, patients become candidates for arthroscopic labral repair. In the last 2 decades, the rate of hip arthroscopy has increased nearly 4-fold. However, as hip arthroscopy is performed more frequently, there is a need for a proper technique to minimize morbidity, because hip arthroscopy has been known to have a steep learning curve. We present a method for arthroscopic hip labral repair using suture anchors without a capsular repair. This Technical Note highlights our technique for labral repair, along with pearls and pitfalls of hip arthroscopy.

Open 4-Compartment Fasciotomy for Chronic Exertional Compartment Syndrome of the Leg.

Chronic exertional compartment syndrome (CECS) is a significant source of lower extremity pain and morbidity in the athletic population. Although endoscopic techniques have been introduced, open fasciotomy remains the mainstay of surgical treatment because of the paucity of evidence in support of an endoscopic approach. The literature on surgical management of CECS is mixed, and overall success rates are modest at best. Optimizing surgical technique, including prevention of neurovascular injury and wound complications, can make a significant impact on the clinical outcome. Here we present our surgical technique, including pearls and pitfalls, for open 4-compartment fasciotomy for treatment of chronic exertional compartment syndrome.