Knee Pain and Functional Outcomes after Retrograde Femoral Nailing: A Retrospective Review.

) 218( COPYRIGHT 2021 © BY THE ARCHIVES OF BONE AND JOINT SURGERY RESEARCH ARTICLE Knee Pain and Functional Outcomes after Retrograde Femoral Nailing: A Retrospective Review Garrett Breyer, BS; Kudret Usmani, MD; Rock Hwang, MD; Brian Begley, BA; Rakesh P. Mashru, MD; Christina J. Gutowski, MD, MPH Research performed at Cooper University Healthcare, Camden, NJ, USA Received: 21 September 2022 Accepted: 10 November 2022 Abstract Objectives: To investigate the incidence and severity of knee pain following retrograde intramedullary nailing of femur fractures and to better understand functional outcomes using validated patient-reported outcome measures. Methods: Fifty-three patients with OTA 32 or 33 fractures treated by retrograde nail at a single academic Level 1 trauma center between 2009 and 2020 were retrospectively reviewed. Patients verbally completed the Oxford Knee Score (OKS) and Patient-Reported Outcome Measurement Information System (PROMIS) Short Form 6b, minimum one year postoperatively. Results: Thirty-four (64%) patients reported the presence of pain. Of those reporting pain, 16 (47.1%) reported their pain as mild. Compared to those without pain, patients with knee pain had lower OKS (30.38 +/- 10.65, versus 41.95 +/- 6.87; P <0.001) and higher PROMIS scores (14.65 +/- 6.76 versus 10.95 +/- 7.09; P=0.066). Conclusion: The increasing severity of pain was inversely correlated with functional status as measured by patientreported measures. At present, the reliability, high union rates, and otherwise low complication rates associated with retrograde femoral nailing justify its continued use. However, knee pain and functional outcomes should remain an integral part of the preoperative discussion with the patient. Level of evidence: III Keywords: Function, Femur, Intramedullary nail, Knee, Pain, Retrograde, Trauma Introduction F emoral shaft fractures have a national annual incidence of 10 to 21 per 100,000 individuals, with bimodal distribution peaking among younger males and older females.1,2 These injuries demonstrate bimodal distribution with peaks in incidences among younger males (15 – 35 years) and older females (greater than 60 years).1 Femoral shaft fractures in young males are often attributed to high-energy trauma, including motor vehicle collisions, falls from height, and gunshot wounds. In contrast, older females sustain this injury secondary to low energy mechanisms such as falls from standing height, often in the setting of underlying osteoporosis.1,2 Factors that determine surgical management of femoral fractures include the location of the fracture, degree of comminution, presence of concomitant injuries, and preoperative functional status.1 Intramedullary nailing is often favored as these devices are load-sharing, require less soft-tissue Corresponding Author: Garrett Breyer, Cooper Medical School of Rowan University, Camden, New Jersey, USA Email: stripping, and allow for earlier mobilization.1,3-6 Antegrade femoral nailing has demonstrated excellent outcomes in the literature with regard to fracture union and early postoperative mobilization. Antegrade nailing, however, is associated with several complications, including Trendelenburg gait, persistent hip pain, and iatrogenic femoral neck fracture.7-14 Retrograde femoral nailing has been shown to be a safe alternative to antegrade nailing, especially in bilateral or distal femur fractures, ipsilateral femoral neck or tibia fractures, obesity, and abdominal and pelvic traumas.10,11,13-20 Union rates have not shown to be statistically different between approaches.11 While outcomes have been favorable, retrograde femoral nailing is not without its own shortcomings. Reported adverse associations include postoperative knee pain, knee arthrosis, and knee septic arthritis.7,16–18,21,22 In particular, postoperative knee pain is often cited as an THE ONLINE VERSION OF THIS ARTICLE ABJS.MUMS.AC.IR Arch Bone Jt Surg. 2023; 11(3): 218-224 Doi: 10.22038/ABJS.2022.67164.3215 http://abjs.mums.ac.ir (219) THE ARCHIVES OF BONE AND JOINT SURGERY. ABJS.MUMS.AC.IR VOLUME 11. NUMBER 3. MARCH 2023 adverse outcome of retrograde nailing, with reported rates varying from 20 to 70%.6,11,12,23,24 In such studies, knee pain is often considered as a binary variable (either present or absent). The quantitative severity of pain, the qualitative nature of pain, and the long-term impact on quality of life have rarely been measured. To our knowledge, few studies report the consequences of knee pain after retrograde femoral nailing in terms of function and patient-reported outcomes, and none utilize the PROMIS scoring system, which is a validated instrument for assessing orthopaedic trauma patients.25,26 With knee pain rates cited as high as 70%, a better understanding of knee pain and resultant function is essential. This study aims to investigate the incidence and severity of knee pain following retrograde nailing and to better understand consequent functional limitations using validated outcomes tools. Materials and Methods This study was approved by the authors’ Institutional Review Board )IRB). The institution’s patient database was queried using Current Procedural Terminology (CPT) codes to identify 1402 patients who underwent femoral intramedullary nailing between January 2009 and December 2020 at a single Level I trauma center. The accuracy of this query was confirmed through radiographic verification. Inclusion criteria included patients 18 years and older treated with retrograde femoral nails for OTA 32 or 33 fractures.27 Exclusion criteria included patients younger than 18 years of age, pre-existing osteoarthritis of the knee, documented previous or concomitant articular knee injury, history of previous knee surgery, pathologic fracture, or history of subsequent knee injury at a date after the index procedure. Of the original 1402 patients, 442 patients met all criteria. Relevant demographic and clinical data were recorded. Following the chart review, a telephone interview was conducted utilizing an IRB-approved telephone script. After obtaining consent, a verbal survey was administered inquiring about knee pain, stiffness, and their subjective perceptions of limb length as well as knee range of motion. Patients then verbally completed the Oxford Knee Score (OKS) and the Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function Short Form 6b. Patients were mailed a review of the study, a copy of the consent form, and contact information for study personnel. Fifty-three patients were ultimately able to be contacted, agreed to participate in the survey, and were Knee Pain and Functional Outcomes after R-IMN included in the final analysis. Primary outcome variables were OKS and PROMIS assessments. OKS is a 12-item patient-reported survey scored on a scale from 0 (most severe symptoms or worst outcome) to 48 (best outcome), designed to assess function and pain after total knee a (...truncated)