Fascia Iliaca Blockade With the Addition of Liposomal Bupivacaine Versus Plain Bupivacaine for Perioperative Pain Management During Hip Arthroscopy: A Double-Blinded Prospective Randomized Control Trial.

PURPOSE: To determine in a prospective, randomized fashion whether liposomal bupivacaine extends the effectiveness of decreased pain scores and reduces narcotic requirements following hip arthroscopy when used in addition to a fascia iliaca blockade with plain bupivacaine alone. METHODS: Double-blinded prospective randomized controlled trial of participants undergoing hip arthroscopy. Randomized to receive a fascia iliaca blockade with 40 mL 0.25% plain bupivacaine (100 mg; control group) or 20 mL 0.5% plain bupivacaine (100 mg) plus 20 mL liposomal bupivacaine (266 mg; study group). The primary outcome was Defense and Veterans Pain Rating Scale (DVPRS) scores in the postanesthesia care unit and on postoperative days (POD) 1, 2, 3, and 14. Secondary outcomes included postoperative opioid consumption and subjective loss of anterior thigh sensation. RESULTS: Seventy-four patients were enrolled, and 70 completed the study; 37 were randomized to the control group and 33 to the study group. There was no significant difference in postoperative DVPRS scores at any time point. There was no significant difference in total postoperative opioid use during any postoperative time points. While most patients reported anterior thigh numbness at discharge, significantly more patients in the study group reported anterior thigh numbness at POD2 (control, 19/37 numb vs study, 32/33 numb; P < .0001) and at POD3 (control, 8/37 numb vs study, 26/33 numb; P < .0001). CONCLUSIONS: In this prospective evaluation comparing plain bupivacaine versus the liposomal formulation administered via a fascia iliaca blockade there were no significant differences in postoperative pain scores and narcotic pill usage. Given the highly significant findings of prolonged anterior thigh numbness out to POD3 in patients who received liposomal bupivacaine, this formulation did exhibit prolonged effects; however, it did not provide improved pain control when used in this surgical population, likely due to the innervation of the hip capsule from differential nerve plexi. Given the 6-fold increased cost of using the liposomal formulation, we are unable to recommend its use via a fascia iliaca blockade for hip arthroscopy. LEVEL OF EVIDENCE: Level I, therapeutic study.

Reaction Time and Brake Pedal Depression Following Arthroscopic Hip Surgery: A Prospective Case-Control Study.

PURPOSE: The purpose of this study was to determine whether patients diagnosed with femoroacetabular impingement (FAI) syndrome have prolonged braking times compared with age- and gender-matched controls and how long after surgery braking times return to preoperative baseline. METHODS: Fifty-nine patients undergoing arthroscopic hip surgery for FAI and 59 age- and gender-matched controls without FAI were enrolled in a prospective comparative study between September 2015 and October 2016. Total brake reaction time (BRT) and brake pedal depression (BPD) were measured for study patients preoperatively, and at 2, 4, and 6 weeks postoperatively. BRT and BPD were compared between study and control patients and between preoperative and postoperative time periods, using mixed effects models. RESULTS: Patients with FAI had significantly prolonged BRT (but not BPD) prior to surgery compared with controls (568 vs 520 msec, P = .002). For study patients undergoing left hip surgery, there was no difference in BRT or BPD between preoperative measurements and any postoperative time point, including the first postoperative appointment at 2 weeks (563 vs 566 msec, P = .89). Patients undergoing right hip surgery had significantly prolonged BRT at 2 weeks postoperatively compared with their preoperative baseline (688 vs 573 msec, P < .001). By 4 weeks postoperatively, study patients undergoing right hip surgery had returned to their preoperative baseline (573 vs 594 msec, P = .28). No significant effect was seen based on visual analog scale pain score, opiate usage, or patient-reported outcome scores. CONCLUSIONS: Patients undergoing arthroscopic surgery of the right hip show significantly prolonged BRT until 4 weeks after surgery, while patients undergoing surgery of the left hip show no postoperative impairment in either BRT or BPD. The clinical relevance of this measured difference (an increase in 10 feet of stopping distance at 60 miles per hour) remains an open question. LEVEL OF EVIDENCE: Level II, diagnostic, prospective.

rhBMP-2 and Intramedullary Fixation in Congenital Pseudarthrosis of the Tibia.

BACKGROUND: In congenital pseudarthrosis of the tibia, use of intramedullary (IM) fixation and autogenous bone graft has long been the standard of care. This study was undertaken to determine whether the addition of rhBMP-2 to this treatment method further enhances healing potential. METHODS: Twenty-one patients with congenital pseudarthrosis of the tibia were evaluated. Fifteen of these patients had neurofibromatosis type 1 (NF1). All had IM fixation and autogenous bone graft, followed by a BMP-soaked collagen sponge wrapped around both the fracture site and bone graft. A minimum 2 years' follow-up was required. RESULTS: Follow-up averaged 7.2 years (range, 2.1 to 12.8 y). Sixteen of 21 tibias achieved bone union following the index surgery, at an average 6.6 months postoperatively. The 5 persistent nonunions occurred in NF1 patients. Further surgery was undertaken in these 5 NF1 patients, including the use of BMP. One of the 5 healed, 1 had persistent nonunion, and 3 eventually had amputation. Of the 16 patients who healed initially following the index surgery, 5 refractured (3 had NF1). Of these 5 patients, the IM fixation at the index surgery did not cross the ankle joint, and refracture occurred at the rod tip in 4. Three of these 5 patients healed following further surgery, 1 had persistent nonunion, and 1 had amputation. All of those with eventual amputation had NF1. No deleterious effects related to the use of BMP-2 were recognized in any patient. CONCLUSIONS: The addition of rhBMP-2 appears to be helpful in shortening the time required to achieve fracture union in those who healed, but its use does not insure that healing will occur. LEVEL OF EVIDENCE: Level IV-therapeutic, case series.

Morphological Distribution of the Anterior Inferior Iliac Spine in Patients With and Without Hip Impingement: Reliability, Validity, and Relationship to the Intraoperative Assessment.

BACKGROUND: Subspinous impingement of the anterior inferior iliac spine (AIIS) on the femoral head-neck junction is increasingly recognized as a source of hip impingement. A classification system of AIIS morphology has previously been proposed that correlates with reduced hip motion and may predispose patients to subspinous hip impingement. PURPOSE: To examine the morphological distribution of AIIS types in patients with and without diagnosed hip impingement and correlate AIIS morphology to intraoperative findings at the time of surgery. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Three-dimensional reconstructed pelvic computed tomography scans were generated for a stratified sample of 449 hips in patients without a history of hip pain or hip impingement and 59 hips in patients with a diagnosis of hip impingement. Three blinded assessors classified the AIIS for each hip twice. The morphological distribution between symptomatic and asymptomatic patients was compared, controlling for age, sex, and affected side. Within the symptomatic cohort, AIIS morphology was compared with the intraoperative assessment of a low-lying AIIS using the Fisher exact test. RESULTS: The intraobserver reliability of the classification system in our cohort was substantial (κ = 0.68-0.77). The interobserver reliability was moderate (κ = 0.50). The morphological distribution between symptomatic and asymptomatic patients was similar, with 75% of patients in the asymptomatic group and 80% of the patients in the symptomatic group having a type 2 or type 3 AIIS. When matched for age, sex, and affected side, there was no significant difference in the assessed classification type between the groups ( P = .55). Within the symptomatic group, there was no significant correlation between the surgeon assessment of a low-lying AIIS and a type 2 or type 3 radiographic classification ( P = .10). The positive predictive value of a type 2 or type 3 AIIS classification for hip impingement symptoms was 10%, and the negative predictive value was 91%. CONCLUSION: These findings suggest that a high percentage of patients with AIIS morphology associated with subspinous impingement are, in fact, asymptomatic. The current radiographic classification scheme should not be used exclusively for clinical decision making.

Outcomes of Hip Arthroscopy in the Older Adult: A Systematic Review of the Literature.

BACKGROUND: The indications for hip preservation surgery have expanded to include treatment of hip pathology in older adults. While several studies have examined the efficacy of hip arthroscopy in the setting of osteoarthritis, there has been no review of outcomes in older adults. PURPOSE: To review the outcomes of hip arthroscopy in older adults and identify factors associated with treatment failures. STUDY DESIGN: Systematic review. METHODS: PubMed, EMBASE, and the Cochrane Library were searched through March 2016 for studies reporting outcomes of primary hip arthroscopy in patients older than 40 years. Inclusion in the review was based on age, patient-reported outcome (PRO) measures, and duration of follow-up. Two authors screened the results and extracted data for use in this review. Standardized mean difference was calculated to estimate effect size for PRO scores within studies. RESULTS: Eight studies with 401 total patients undergoing hip arthroscopy for femoroacetabular impingement (FAI) or labral tears were included in this review. Seven of the 8 studies reported favorable PRO scores and significant postoperative improvement with moderate to large effect size. The included studies demonstrated a trend toward higher effect sizes with an increasing percentage of labral repair compared to isolated labral debridement. The complication rate was comparable to that of previous reports involving younger patients; however, the overall reoperation rate was 20.8%. Conversion to hip arthroplasty ranged from 0% to 30%, with an overall conversion rate of 18.5% at a mean time of 17.5 months following arthroscopy. The most common risk factors for conversion to arthroplasty were low preoperative PRO scores and advanced arthritis. CONCLUSION: Hip arthroscopy appears to be a safe and efficacious treatment for labral tears and FAI in older patients who do not have significant underlying degenerative changes. However, in this population, there is a significant proportion of patients who eventually require hip arthroplasty. Outcomes may be affected by type of treatment (ie, labral debridement vs repair). Additional high-quality studies are needed to understand how these factors affect outcomes.

Analysis and comparison of the biomechanical properties of univalved and bivalved cast models.

PURPOSE: Fiberglass casts are frequently valved to relieve the pressure associated with upper extremity swelling after a surgical procedure or when applied after reduction of a displaced fracture in a child. Although different opinions exist regarding the valving of casts, no research to date has explored the biomechanical effects of this commonly used technique. As cast integrity is essential for the maintenance of fracture reduction, it is important to understand whether casts are structurally compromised after valving. Understanding the effects of valving on cast integrity may help guide clinicians in the technique of valving while minimizing the potential for a loss of fracture reduction. METHODS: Thirty standardized cylindrical fiberglass cast models were created. Ten models were left intact, 10 were univalved, and 10 were bivalved. All the models were mechanically tested by a 3-point bending apparatus secured to a biaxial materials testing system. Load to failure and bending stiffness were recorded for each sample. Differences in load of failure and bending stiffness were compared among the groups. RESULTS: Unvalved cast models had the highest failure load and bending stiffness, whereas bivalved casts showed the lowest value for both failure load and bending stiffness. Univalved casts had a failure load measured to be between those of unvalved and bivalved cast models. Analysis of variance showed significance when failure load and bending stiffness data among all the groups were compared. A post hoc Bonferroni statistical analysis showed significance in bending stiffness between intact and bivalved models (P < 0.01), intact and univalved models (P < 0.01), but no significant difference in bending stiffness between univalved and bivalved models (P > 0.01). Differences in measured failure load values were found to be statistically significant among all cast models (P < 0.01). CONCLUSIONS: Valving significantly decreases the bending stiffness and load to failure of fiberglass casts. Univalved casts have a higher load to failure than bivalved casts. CLINICAL RELEVANCE: Valving adversely alters the structural integrity of fiberglass casts. This may impair a cast's ability to effectively immobilize an extremity or maintain a fracture reduction.

Intraosseous innervation of the human patella: a histologic study.

BACKGROUND: The soft tissue structures surrounding the human knee joint have been the subject of extensive anatomic study. The detailed histologic findings within the bone of the human patella, however, have not been systematically studied. While the nerves supplied to the periarticular soft tissues have been very well documented, the nerves supplied to the interior of the bony patella have never been described. HYPOTHESIS: This study tests the hypothesis that the patella contains an intraosseous nerve network. Further, the authors investigate the anatomic location of these intraosseous nerves to better understand their possible clinical relevance. STUDY DESIGN: Descriptive laboratory study. METHODS: Ten matched pairs of cadaveric patellae (left and right patellae from the same individual; 20 total) were prepared for evaluation by hematoxylin and eosin staining using a technique that allows the creation of complete, large histologic sections of individual patellae. The matched specimens were dissected free of soft tissue and then sectioned using a diamond-wafering saw into 3-mm sagittal (left patella) and transverse (right patella) sections. Sections were then decalcified and whole-mounted into paraffin blocks for further sectioning using a large-format microtome. All 20 specimens were prepared for evaluation. Age at death averaged 80 years (range, 64-91). All specimens demonstrated at least grade II chondromalacia. RESULTS: Nineteen of 20 (95%) specimens demonstrated intraosseous nerves. Of 248 sections studied, 116 (47%) demonstrated intraosseous nerves, with 227 individual nerves identified. The density of intraosseous nerves was greatest in the medial and central portions of the patella, with a significant paucity identified laterally. CONCLUSION: The primary intraosseous innervation of the patella derives from a medially based neurovascular bundle. CLINICAL RELEVANCE: A better understanding of the nerves within the human bony patella may improve understanding the patho-physiology of anterior knee pain syndromes.