Leukocyte-Poor Platelet-Rich Plasma as a Treatment for Patellar Tendinopathy A Multicenter, Randomized Controlled Trial.

PURPOSE: The purpose of this study was to compare regimens of eccentric exercise and dry-needling, with and without an ultrasound-guided leukocyte-poor platelet-rich plasma (LP-PRP) injection, in patients with patellar tendinopathy. METHODS: Patients with symptomatic patellar tendinopathy based on physical examination and magnetic resonance imaging and who had failed at least 6 weeks of nonoperative treatment were enrolled and randomized at two centers to receive ultrasound-guided dry-needling (DN) alone or in addition to an injection of LP-PRP coupled with standardized eccentric strengthening exercises. Participants completed patient-reported outcome surveys at baseline and at 3, 6, 9, 12, and 26 weeks post-treatment. The primary outcome measure was the Victorian Institute of Sports Assessment (VISA) score for patellar tendinopathy (VISA-P) at 12 weeks, and secondary measures included the visual analog scale (VAS) for pain, Tegner activity scale, Lysholm knee scale (Lysholm), and Veterans Rand 12-Item Health Survey (VR12) questionnaire at 12 and 26 weeks. RESULTS: Thirty-one subjects were enrolled in the study (15 DN, 16 LP-PRP). Twenty-three patients were available for follow-up at all time points. There were no statistically significant differences between the two groups at baseline. At 12 weeks post-treatment, both the LP-PRP and DN groups demonstrated statistically significant (p < 0.05) improvements from baseline with respect to Lysholm score (34.5 ± 15.1 and 31.7 ± 18.4), VAS pain scale (-1.58 ± 2.1 and -2.8 ± 1.9, respectively), and VISA score (19.2 ± 15.9 and 28.4 ± 19.4, respectively). At 26 weeks post-treatment both groups demonstrated statistically significant (p < 0.05) improvements in Lysholm score (23.6 ± 23.1 and 24.5 ± 17.3, respectively) and VAS pain score (-1.67 ± 2.3 and -2.18 ± 2.9, respectively). The LP-PRP group failed to show significance for VISA-P score from 0 to 26 weeks, though the DN group did (22.0 ± 14.6). There were no statistically significant differences between the two groups in mean VISA, VAS, Lysholm, or the Short Form Health Survey (SF-12) scores at either the 12 week or 26-week follow-up time points. CONCLUSION: The results of the current study demonstrate that both DN and DN plus LP-PRP are effective treatment options in the management of symptomatic patellar tendinopathy, however, LP-PRP did not add any additional improvement over DN alone.

Factors Associated with Patient Satisfaction After Periacetabular Osteotomy.

BACKGROUND: The periacetabular osteotomy (PAO) was developed to treat acetabular dysplasia and avoid the progression of osteoarthritis. Prior research has correlated demographic and radiographic variables with postoperative patient outcomes but with limited focus on patient expectations and correlation with satisfaction. The purpose of this study was to determine whether any such associations exist with the PAO. METHODS: An anonymous, de-identified satisfaction survey was applied to patients undergoing a PAO between April 2017 and April 2019. Forty patients (26 females) who underwent PAOs were included in the final analysis. The average age of the cohort was 22.0 ± 5.1 years of age. All patients had a minimum of 12 months of follow-up from the date of surgery. Patient demographics, diagnosis, and complications were recorded. Radiographs were then analyzed to determine pre- and postoperative lateral center edge angle (LCEA) and Tönnis roof angle, and correlations between satisfaction and radiographic analyses were performed. Statistical analysis included non-parametric Spearman's correlation and receiver operator characteristic. Statistical significance was set at p < 0.05. RESULTS: Thirty (75%) patients were satisfied with their outcome. There were no statistically significant associations between patient age or sex and postoperative satisfaction (p > 0.05). The average LCEA was 10.9° ± 6.9° preoperatively and 26.0° ± 4.2° postoperatively with an average change of 15.1° ± 5.6°. The average Tönnis angle was 18.8° ± 3.3° preoperatively, decreasing to 11.6° ± 3.2° postoperatively with an average change of -7.2° ± 3.2°. Interobserver reliability was high, ranging from r = 0.782, p < 0.001 for postoperative Tönnis angle to r = 0.958, p < 0.001 for preoperative LCEA. Preoperative LCEA correlated positively with satisfaction, r = 0.351, p = 0.027. Logistic regression demonstrated that for every increasing degree of preoperative LCEA, odds of postoperative satisfaction increased by 1.13 (95% CI: 1.01 to 1.27), p = 0.034. CONCLUSION: This study suggests that postoperative patient satisfaction after PAO may be associated with preoperative patient demographics such as LCEA. It also suggests that more dysplastic hips may have lower rates of postoperative satisfaction than patients with less severe deformity. These associations warrant further study, which may yield prognostic value for future surgery.

Talk It Out to Walk It Out A Guide for Residents and Medical Students on the Fundamentals of Gait.

Although gait is one of the most globally ubiquitous concepts-traversing all geographic, cultural, and language barriers-it is often seen as an overwhelming and confusing concept. This review describes the phases and components of gait to help the clinician identify what is normal, evaluate what is not normal, and understand some common pathologic gait patterns seen in the different orthopedic subspecialties.

The Role of Distraction Osteogenesis in Limb Salvage for Tumors.

Modern technology and advances in medicine have facilitated increasing rates of limb salvage in the treatment of sarcomas. Orthopedic oncologists have a wide array of reconstruction options for limb salvage, ranging from allografts to endoprosthesis reconstruction. Limb lengthening is another option available to an orthopedic oncologist faced with bony defects and limb length discrepancies following resection. This review provides a brief history of limb lengthening, the principles of distraction osteogenesis, and current applications in orthopedic oncology. Considering the complications and challenges associated with the lengthening process, appropriate patient selection and thorough patient counseling is key to optimizing outcomes.

Parent Reported Perspectives on Pediatric Radiation Exposure in a Pediatric Orthopedic Clinic.

BACKGROUND: Few studies have investigated the perspective of caregivers as it pertains to their children having xrays performed. This study sought to identify which factors contribute to the varying views that caregivers have toward giving their children x-rays. METHODS: The data was collected through an anonymous survey administered during visits to the pediatric orthopedic surgery clinic. The survey was completed by the patient's parent, guardian, or caregiver, and was administered by a treating physician. The data was analyzed using Fisher exact tests. RESULTS: A total of 62 surveys were obtained from caregivers in the pediatric orthopedic clinic. The analysis found that 23.3% of parents reported concerns regarding their child having an x-ray. One hundred percent of those parents that reported concern attributed this to the risk associated with radiation exposure. Along with the radiation exposure risk, 10% believed that another test would be more useful, and 10% were concerned that their insurance did not cover the x-ray procedure. In contrast, 46.8% of the parents felt that their visit would not be complete without having an x-ray. Of this group, 38.5% felt an x-ray was necessary for diagnosis, 19.5% felt something would be missed without the x-ray, and 42% felt concerned about both missing something and not being able to properly diagnose. CONCLUSIONS: This study found that almost 25% of caregivers surveyed expressed concerns regarding the risks of radiation exposure to their child while having an x-ray. This underscores an opportunity to educate caregivers about the risks associated with x-ray radiation exposure as well as to quantify radiation exposure risk from x-ray as compared to ambient environmental radiation exposure. In addition, almost 40% of caregivers felt their visit was incomplete without an x-ray. Thus, it is indispensable for the physician to communicate with the caregiver on the significance of the x-ray and explain whether or not it would be required.

Correction to: Point of Care Ultrasound as Performed by the Clinician for the Enhancement of Physical Examination: A Technique Guide for Developmental Hip Dysplasia.

[This corrects the article DOI: 10.1007/s43465-021-00570-8.].

Point-of-Care Ultrasound Reduces Visit Time and Cost of Care for Infants with Developmental Dysplasia of the Hip.

Background: Healthcare institutions and policymakers are searching for system-wide approaches to reduce costs while maintaining quality and improving patient outcomes. In most healthcare systems infants referred for the detecting or treating developmental dysplasia of the hip (DDH) are sent to a radiology department for sonographic evaluation. The total duration of visit and cost of visit are essential variables in any healthcare setting and affect both efficiency and "the bottom line". By having the treating clinician perform point-of-care ultrasound (POCUS) for the detection and follow-up of patients with DDH, we hypothesize that there would be a significant reduction in the time spent on the visit and the cost incurred without compromising quality or patient satisfaction. To our knowledge, no prior study has examined the effect of incorporating POCUS on the duration and cost of the visit in patients with DDH. Purpose: To determine if there was a difference in the duration of the visit for patients with DDH when POCUS was performed compared to when traditional "formal" sonography was performed. To determine if there was a difference in the cost of the visit for patients with DDH when POCUS was performed compared to when traditional "formal" sonography was performed. Methods: Data for visits to a specialized outpatient office were collected over two years at a single-specialty orthopedic hospital, comparing the duration and cost of the visit between patient encounters for infants who had "formal" sonograms performed in the radiology suite to infants who underwent POCUS of the hip. In all, we included 532 patient encounters, 326 patients had POCUS performed, and 206 had a "formal" ultrasonographic evaluation performed. Of these, 140 were new evaluations and 392 were follow-up evaluations for treatment. Of the 140 new patients, 80 were in the POCUS group, and 60 were in the "formal" US group. Of the 392 follow-ups, 246 were in the POCUS group, and 146 were in the "formal" US group. Results: The mean duration of the encounter for the POCUS group was 42 min (range 16-75 min), and for the "formal" US group, it was 92 min (range 36-163 min). This difference was statistically significant (p = 0.002). The mean cost of the encounter for the POCUS group was $121.13, and for the "formal" US group, it was $339.38. This difference was statistically significant (p = 0.002). Conclusion: Ultimately, our study demonstrated a statistically significant reduction in the duration and cost of a patient encounter for infants with DDH when they undergo POCUS rather than "formal" sonographic evaluation.

Modified Oxford Bone Scores Are Reduced in Patients With Slipped Capital Femoral Epiphysis Compared With Healthy Controls.

BACKGROUND: The etiology and pathogenesis of slipped capital femoral epiphysis (SCFE) are attributable to abnormalities of the proximal femoral epiphysis. This study aimed to examine if there is a difference in the bone age of patients diagnosed with SCFE compared with patients without hip pathology. METHODS: We identified a consecutive series of patients treated for SCFE between December 2012 and December 2019 from a departmental database. Retrospective chart review was performed to collect demographic information and patient medical history. We then obtained a control group of statistically similar patients based on age and sex. These patients did not have hip pathology or medical comorbidities that could alter their bone age. The modified Oxford bone score (mOBS) was calculated for both groups by 3 blinded reviewers. We excluded patients with unstable slips, endocrine disorders, and inadequate imaging. RESULTS: We identified 60 patients with stable idiopathic SCFE during the study period; 45 met inclusion criteria and were included in the final analysis. There were 27 males and 18 females. The average age of patients with SCFE was higher in males than females (12.6 vs. 11.1, P<0.01). Patients in the comparison cohort did not differ significantly from the SCFE cohort in terms of age (11.6 vs. 12.0, P=0.06) or sex (P=0.52). The comparison group's median mOBS was significantly higher than the SCFE group (22.5 vs. 20.5, P<0.01). The difference in the mOBS between male and female patients in the SCFE group approached significance (20.0 vs. 21.0, P=0.05). The weighted κ coefficient was 0.93. CONCLUSIONS: Patients with SCFE have a decreased bone age compared with patients without hip pathology. Male patients with SCFE were more likely to be older compared with female patients. LEVEL OF EVIDENCE: Level IV-retrospective study.

Real-Time Fluoroscopic Navigation Improves Acetabular Component Positioning During Direct Anterior Approach Total Hip Arthroplasty.

We investigated whether a novel, real-time fluoroscopybased navigation system optimized component positioning and leg length in fluoroscopically aided direct anterior approach total hip arthroplasty (DAA-THA). We retrospectively reviewed 75 fluoroscopically assisted DAA-THA performed by a single surgeon: 37 procedures used the software intraoperatively to overlay anteversion, inclination, and leg length information over the existing fluoroscopic radiograph with the aim of enhancing component positioning. The control group consisted of 38 procedures from the single surgeon's patient pool who had undergone non-navigated fluoroscopic assisted DAA-THA 1 month prior to the system's trial. Our results demonstrate that the navigation group measurements were significantly closer to the target numbers with less variation. The mean difference from target value were as follows: for anteversion (control: -4.68°, navigated: -01.0°), inclination (control: -1.87°, navigated: 0.8°), and leg length discrepancy (control: -2.59°, navigated: -0.98°). In addition, surgical time was shorter in the navigation group (75.7 vs. 74 minutes; p = 0.001). The real-time feedback and calculations provided by the navigation software provided a reproducible precision for component positioning and leg length measurement during DAA-THA.

Patient Satisfaction Is Equivalent Using Telemedicine Versus Office-Based Follow-up After Arthroscopic Meniscal Surgery: A Prospective, Randomized Controlled Trial.

BACKGROUND: Telemedicine has increasingly been considered as a viable alternative to traditional office-based health care, including postoperative follow-up visits. The purpose of the present study was to determine if patient satisfaction with overall care is equivalent for telemedicine follow-up (i.e., synchronous face-to-face video) and office-based follow-up after arthroscopic meniscectomy and repair. METHODS: Patients were prospectively enrolled from August 1, 2019, to March 1, 2020. Patients were included who were ≥18 years old, consented to isolated arthroscopic meniscal repair or meniscectomy, and were able to properly utilize telemedicine software on a computer, tablet, or smartphone with a built-in camera. Patient demographic data, including complication events and postoperative satisfaction data, were recorded and analyzed for significance. RESULTS: One hundred and fifty patients were enrolled in the study, of whom 122 (81.3%) were included in the final analysis. There were no significant differences between groups in terms of patient demographics or satisfaction scores. Patient satisfaction with overall care was equivalent based on the results of two 1-sided t-test analysis for equivalence (9.77 ± 0.60 in the office-based group versus 9.79 ± 0.53 in the telemedicine group; p < 0.001). When patients were asked to indicate their preferred follow-up type with the options listed as the type they received versus an alternative, 58 patients (84.1%) in the office-based group preferred their received type of follow-up, whereas 42 (79.2%) in the telemedicine group preferred their received follow-up (p = 0.493). There were no significant differences between groups in terms of complications (p > 0.05). CONCLUSIONS: The present study showed that patient satisfaction with overall care is equivalent between telemedicine and office-based follow-up in the immediate postoperative period following an arthroscopic meniscal surgical procedure, and should be considered a reasonable alternative to the traditional in-office modality. LEVEL OF EVIDENCE: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Point of Care Ultrasound as Performed by the Clinician for the Enhancement of Physical Examination: A Technique Guide for Developmental Hip Dysplasia.

Developmental dysplasia of the hip (DDH) is the most common anatomical pathology present in newborns. DDH is the most common orthopaedic disorder in newborns, with incidences cited from 4.4% to 51.8% depending on risk factors, populations and method of reporting. Traditionally, the standard physical exam for newborns includes the Barlow and Ortolani maneuvers. If either is positive by the pediatrician, the baby is then sent for evaluation by a pediatric orthopaedic surgeon. At this stage, either the pediatrician or pediatric orthopaedic surgeon obtains an ultrasound-the gold standard for DDH diagnosis. When early identification and treatment are not in place, it can lead to significant consequences on an individual's health and financial and public health implications for society at large. This is a detailed technique guide aimed to help physicians consistently perform thorough US evaluations of pediatric hips in order to successfully screen, diagnosis and manage treatment of DDH. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s43465-021-00570-8.

Early Experience with Virtual Pediatric Orthopedics in New York CityPearls for Incorporating Telemedicine into Your Practice.

BACKGROUND: The purpose of this study was to identify and characterize challenges and benefits to the use of tele-medicine for the treatment of pediatric orthopedic patients during and after the COVID-19 pandemic. METHODS: A novel survey was sent to all faculty members at an academic pediatric orthopedic practice in New York City regarding their use of telemedicine in response to the COVID-19 pandemic. RESULTS: Faculty members performed 227 unique tele-health visits with pediatric orthopedic patients over a 7-week period in early 2020, and this formed the basis for responses to the survey. The results of the faculty survey suggest that telemedicine has substantial clinical benefits for pediatric orthopedic surgeons and our patients that extend beyond the COVID-19 pandemic. Providers recognize the limits of conducting physical exams over telemedicine and should always use clinical judgment when evaluating patients, par-ticularly trauma patients who may require prompt referral for additional care. CONCLUSIONS: The ability to provide pediatric orthopedic care through telemedicine has allowed us to safely evaluate and treat pediatric patients with musculoskeletal problems in New York City and its environs despite the COVID-19 pandemic. The efficient evaluation of both new and exist-ing pediatric orthopedic patients via telehealth is viable. Physical examination is the most challenging aspect of the physician-patient encounter to replicate virtually. Targeted educational efforts for patients and their families before the visit about what to expect and how to prepare improves efficiency with virtual pediatric orthopedic visits. Efforts to limit disparities in access to telemedicine will be needed to allow all pediatric orthopedic patients to participate in telemedicine equitably.

Smoking cessation correlates with a decrease in infection rates following total joint arthroplasty.

BACKGROUND: The impact of tobacco use on perioperative complications, hospital costs, and survivorship in total joint arthroplasty (TJA) is well established. The aim of this study is to report the impact of tobacco cessation on outcomes after TJA and to measure the impact of a voluntary smoking cessation program (SCP) on self-reported smoking quit rates in a premier academic medical center. METHODS: A seven-year (2013-2019) SCP database was provided by the Integrative Health Promotion Department and Infection Prevention and Control Department. We evaluated program and smoking status, patient demographics, length of stay (LOS), and 90-day post-operative infection rates and readmission rates. The primary outcome was quit rates based on SCP enrollment status. The secondary outcomes measured infection rates, readmission rates, and LOS based on enrollment status and/or quit rate. RESULTS: A total of 201 eligible patients were identified: 137 patients in the SCP (intervention) group and 64 in the self-treatment (control) group. SCP patients trended towards higher quit rates (43% vs 33%, p = 0.17), shorter LOS (2.47 vs 2.62 days, p = 0.52), lower infection rates (7.3% vs 12.5%, p = 0.27) and slightly higher readmission rates (5.8% vs 4.7%, p = 0.73). In a sub-analysis, self-reported smokers demonstrated statistically significant decrease in infection (3.7% vs 12.5%, p = 0.03). CONCLUSION: There was a statistically significant decrease in infection rates in patients who self-reported quitting tobacco prior to TJA. Additionally, quit rates for patients who participated in a voluntary SCP trended towards increased pre-operative cessation. Further efforts to increase tobacco cessation prior to TJA and examine the impact on patient outcomes are needed.

Synovial Chondromatosis in Patient Presenting with Chronic Venous Stasis Ulcers.

Synovial chondromatosis (SC) is a rare, benign synovial growth most frequently involving the knee or hip joint. Common presenting symptoms include pain throughout the affected joint, reduced range of motion, and a palpable mass. We present an unusual case of SC presenting with symptoms of chronic venous stasis ulcer. A 49-year-old patient presented with swelling, hyperpigmentation, and ulcerations of his right lower extremity. Work-up including duplex and computed tomography scan revealed a calcified mass in the hip joint, highly suspicious for SC. A joint surgical approach from a vascular and orthopedic surgeon successfully removed the growths and decompressed the surrounding vessels. The mass effect of the SC on overlying veins resulted in obstruction of venous return due and subsequent venous stasis ulcerations and symptoms of venous hypertension. We present this case due to the unique vascular sequelae related to the SC to explore this as a new diagnosis to consider in patients who present with venous stasis ulceration and radiographic findings consistent with SC.

Vancomycin Povidone-Iodine Protocol Improves Survivorship of Periprosthetic Joint Infection Treated With Irrigation and Debridement.

BACKGROUND: Irrigation and debridement with modular component and liner exchange (IDLE) is a low morbidity procedure for treatment of periprosthetic joint infection (PJI) with reported failure rates exceeding 50%. Dilute povidone-iodine lavage has been shown to be safe and effective in decreasing acute PJI in primary total joint arthroplasty. Vancomycin powder has also shown to be effective in preventing infection in spine surgery. We hypothesize that a vancomycin povidone-iodine protocol (VIP) used in conjunction with IDLE can increase infection-free survivorship after acute PJI. METHODS: This is a single institution retrospective review of all PJIs treated with IDLE and VIP since March 2014. A consecutive matched control group of patients treated with IDLE for PJI for 2 years prior to March 2014 was also included for analysis. Primary outcome was failure, defined as return to operating room for an infection-related problem. Secondary outcome was chronic suppression with antibiotics at final follow-up. Minimum follow-up was 1 year. RESULTS: A total of 36 patients in the VIP group and 38 patients in control group were identified. In the VIP group, 16.7% (6/36) failed at final follow-up compared to 37% failure rate (14/38) in the control group (P < .05). Three patients in the VIP group were on chronic antibiotic suppression at final follow-up. There were no medical complications secondary to the VIP. CONCLUSIONS: The VIP group demonstrated a significant reduction in reinfection and failure rate following IDLE. The authors believe that a VIP is an effective adjunct for treating PJI with irrigation and debridement.

A Crosswalk Between UCLA and Lower Extremity Activity Scales.

BACKGROUND: The University of California, Los Angeles (UCLA) activity scale and the Lower Extremity Activity Scale (LEAS) are the two most-widely used and rigorously developed scales for assessing activity level in patients having joint replacement. However, the two scales are not convertible, and the level of correlation between the two is not clear. Creating a crosswalk between these scales; that is, a concordance table to convert scores from one scale to the other and vice versa, will help compare results from existing studies using either scale, and pool those results for meta-analyses. It also will facilitate pooling data from multiple registries and data sources. QUESTIONS/PURPOSE: To create a crosswalk between the UCLA and the LEAS activity scales for patients having THA or TKA. METHODS: Preoperative and 2-year postoperative UCLA and LEAS scores for a cohort of patients undergoing primary TKA or THA at the Hospital for Special Surgery between May 2007 and December 2011 were matched from two registries. The scales were self-administered by patients. Three hundred sixty-four patients having TKAs (67% women; mean age, 67 years) and 403 having THA (66% women; mean age, 66 years) had both scores available. The equipercentile equating method was used to create the crosswalk. The standard response mean was used to assess responsiveness of the converted versus actual UCLA and LEAS scores from baseline to 2 years. Crosswalk validation also included comparing the area under the receiver operating characteristic curve of the actual and converted scores to evaluate their ability to discriminate different levels of function measured using the Hip dysfunction and Osteoarthritis Outcome Score activities of daily living subscale for patients having THA and the Knee injury and Osteoarthritis Outcome Score activities of daily living subscale for patients having TKA. Difference between scores was assessed using the inequality test. RESULTS: For patients having TKA, converted mean scores (UCLA to LEAS, 9.5 ± 3.0; LEAS to UCLA, 4.7 ± 2.1) were not different from the actual scores (UCLA, 4.8 ± 2.1; LEAS, 9.4 ± 2.9). Standard response means for the converted scores (UCLA to LEAS, 0.47; LEAS to UCLA, 0.52) were not different from those of the actual scores (UCLA, 0.48; LEAS, 0.56). The areas under the receiver operating characteristic curve also were not different for actual and converted scores for THA and TKA. CONCLUSION: We have developed and validated a crosswalk to easily convert UCLA to LEAS scores (and vice versa) for THA and TKA. Reproducing the crosswalk for other lower extremity conditions or surgical procedures may extend its utility to studies assessing activity in patients having these conditions or procedures.

Is There a Threshold for Stiffness Complaints Following TKA on the WOMAC Stiffness Subscale?

BACKGROUND: Stiffness complaints after total knee arthroplasty (TKA) are frequent, yet poorly understood and can be challenging for surgeons to address. The WOMAC stiffness subscale is a widely used measure of stiffness and can serve as a simple screening tool for complaints. QUESTIONS/PURPOSES: We aimed to identify a threshold for stiffness complaints on the WOMAC stiffness subscale and investigate its overlap with range of motion (ROM) in TKA patients. METHODS: TKA patients were enrolled preoperatively and followed for 6 months. At follow-up, patients reported their ROM, completed the WOMAC stiffness subscale (range 1-8 with 8 continuous stiffness) and indicated whether they experienced more stiffness than expected. To identify a threshold for complaints, we compared patients' WOMAC stiffness scores to when they experienced more stiffness than expected, visually, and statistically. We also mapped ROM limitations at 6 months to WOMAC stiffness scores. Finally, we determined if baseline characteristics were associated with stiffness complaints. RESULTS: Two hundred and forty-six TKA patients were enrolled preoperatively with 82% follow-up rate at 6 months. Our results showed that patients with a WOMAC stiffness score = 3+ were significantly more likely to experience more stiffness than expected. Patients reporting full ROM (54%) reported a wide range of WOMAC stiffness subscale scores (1-6). Baseline WOMAC pain and function scores were the only factors associated with stiffness complaints. CONCLUSIONS: ROM is a poor surrogate of patient-reported stiffness, and the patients' perception of "stiffness" is clearly more complex than just ROM. We identified a WOMAC threshold that could potentially easily serve this purpose.