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Knee Pain and Leg-Length Discrepancy After Retrograde Femoral Nailing Ricardo Reina, MD, Fernando E

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Knee Pain and Leg-Length Discrepancy After Retrograde Femoral Nailing Ricardo Reina, MD, Fernando E (aspects of trauma • an original study) Knee Pain and Leg-Length Discrepancy After Retrograde Femoral Nailing Ricardo Reina, MD, Fernando E. Vilella, MD, Norman Ramírez, MD, Richard Valenzuela, MD, Gil Nieves, MD, and Christian A. Foy, MD ABSTRACT an antegrade entry point at the pirifor- MATERIALS AND METHODS We retrospectively studied postop- mis fossa.1,2,4,8-12 This technique has Between October 1998 and April 2000, erative knee function and leg-length several drawbacks, including a dif- a surgeon at University of Puerto Rico discrepancy (LLD) in 31 patients ficult starting point at the piriformis District Hospital and Puerto Rico with femoral diaphyseal fractures fossa, postoperative Trendelenburg Medical Center used retrograde IMN treated with retrograde intramedul- gait, iatrogenic fracture of the femo- to treat 46 femoral shaft fractures con- lary nailing (IMN) between October 1998 and April 2000. Mean follow-up ral neck, need for a fracture table secutively. For the purpose of this study, was 25 months, mean knee range of with difficult patient positioning, and we selected only those fractures motion was 126°, mean Hospital for limitations in use with concomitant located both 5 cm below the lesser Special Surgery knee scores were surgical procedures.3,5,6 trochanter14 and above the femoral 89.2 (pain) and 78.3 (function), and Over the past 20 years, retrograde condyles. Patients were contacted by mean LLD was 1.19 cm. Despite the IMN has emerged as an alternative telephone, by mail, or through local theoretically higher knee pain and that overcomes the shortcomings of government agencies. LLD rates associated with retrograde antegrade IMN in treating femoral Of the 46 patients, 15 (33%) were IMN, we believe it may offer a viable shaft fractures.1,3-5,7,8,13,14 The advan- excluded (4 had passed away, and 11 treatment option when the antegrade nailing technique is restricted. ractures of the femoral shaft “...indications for retrograde intramedullary are associated with high- nailing have expanded...” energy trauma. Different treatments have had varied Fresults.1-3 Closed intramedullary nail- tages of retrograde IMN include no had insufficient follow-up because of ing (IMN) has been shown to be an need for fracture table, ease of entry poor patient compliance, or they were effective treatment, with high success at the intercondylar notch, and acces- unavailable for evaluation at a specif- rates and minimal complications.1-8 sibility for performing additional ic clinic). The remaining 31 patients The current standard of care for surgical procedures with the patient (67%) had a minimum follow-up of 1 femoral shaft fractures is IMN through in a supine position.5 The original year and were evaluated by the senior indications for retrograde IMN were authors at a clinic specially set up Dr. Reina is in private practice, San Juan, femoral shaft fractures with ipsilat- for this study. In accordance with the Puerto Rico. eral femoral neck fractures, femoral approved protocol of our Institutional Dr. Vilella is Third-Year Resident, Dr. shaft fractures in polytrauma patients, Review Board, all patients received a Ramírez is Director of Research, Dr. and obese patients.1,2,7-9,14 With the complete orientation to the study and Valenzuela and Dr. Nieves are First- advantages of this technique, indi- signed release and consent forms for Year Residents, and Dr. Foy is Research Fellow, Department of Orthopaedic cations for retrograde IMN have participation. Surgery, School of Medicine, University expanded. The increasing popularity The medical records of these of Puerto Rico, San Juan, Puerto Rico. of the procedure has raised concerns patients were reviewed for vari- in the orthopedic community about ables such as accident type, associ- Requests for reprints: Norman Ramírez, MD, Department of Orthopaedic Surgery, possible complications with respect ated injuries, degree of comminution, School of Medicine, University of Puerto to knee function, knee pain, and leg- open fracture classification, compli- Rico, San Juan, PR 00936 (tel, 787-264- length discrepancy (LLD) secondary cations, and need for concomitant 2066; fax, 787-264-4483; e-mail, norman- to the procedure.4,6 surgical procedures. For each patient, [email protected]). In the study reported here, we the Winquist and Hansen classifica- Am J Orthop. 2007;36(6):325-328. reviewed postoperative knee function tion for comminution of femur frac- Copyright Quadrant HealthCom Inc. and LLD after retrograde IMN for tures was used: 0 (no comminution), 2007. femoral diaphyseal fractures. 1 (insignificant butterfly fragment), June 2007 325 Pain and Leg-Length Discrepancy After Retrograde Femoral Nailing In each patient, a scanogram was included for evaluation in the study. obtained to objectively determine Minimum follow-up was 1 year, LLD, defined as more than a 2-cm and mean follow-up was 25 months difference between the legs.9 (range, 12-38 months). Mean age was 33.9 years (range, 18-80 years). Surgical Technique There were 17 right and 10 left femur Each patient was placed on a radio- fractures, and 4 patients had bilat- lucent operating room table in supine eral femur fractures. The most com- position, and the affected lower mon fracture mechanism was motor extremity was prepped and draped in vehicle accident (70%) (Figures 1A, standard surgical fashion. 1B), followed by gunshot wound The knee was positioned in 40° of (17%) (Figures 2A, 2B) and fall from flexion with a bolster, and a 4-cm skin a height (13%). Ten (29%) of the 35 incision was made just medial to the fractures were open: 3 of these were patellar tendon, from the inferior pole type I, 5 were type II, and 2 were type of the patella to the tibial tubercle. III. There were 18 Winquist grade 0 The infrapatellar fat pad was partially fractures, 4 Winquist grade 1 frac- excised, and then a medial patellar tures, 6 Winquist grade 2 fractures, knee arthrotomy was performed. 4 Winquist grade 3 fractures, and 3 With the help of the fluoroscope, a Winquist grade 4 fractures. guided pin was inserted in the mid- Eleven patients had multiple inju- line just anterior to the intercondylar ries, and 20 had isolated femur frac- A B notch in the anteroposterior view. In tures. Associated injuries included Figure 1. Twenty-year-old man with the lateral view, the pin should be head trauma (2 patients), peroneal distal shaft femur fracture sustained above the Blumensaat line. A cannu- nerve palsies (2 patients), vascular in a motor vehicle accident. Antero- lated drill was used to open the dis- injuries (2 patients), 1 radioulnar posterior (A) and lateral (B) plain tal femur metaphysis. A ball-tipped fracture, 1 humeral fracture, 1 pilon films obtained 24 months after ret- guide wire was inserted through the fracture, 1 simultaneous talus and cal- rograde intramedullary nailing show fracture union. entry points just to the distal fracture caneous fracture, 1 acetabular frac- border. After the fracture was reduced, ture, 1 odontoid fracture, 1 abdominal 2 (large butterfly fragment less than the guide wire was introduced across trauma, 1 pneumothorax, 1 testicular 50% the width of the bone), 3 (large the fracture to maintain the alignment contusion, and 1 urethral injury. butterfly fragment more than 50% of the reduction. Flexible reaming the width of the bone), 4 (segmental was performed until adequate cortical comminution). Open fractures were contact was achieved. classified according to Gustilo and For implants, Russell-Taylor femo- Anderson: type I, low-energy trauma ral nails (Smith & Nephew Richards, with wound size less than 1 cm; Memphis, Tenn) were used. The type II, moderate-energy trauma with intramedullary nail was placed to wound size 10 cm or less; type III, a level below the lesser trochanter high-energy trauma with wound size proximally and flush to the chondral more than 10 cm. surface distally. The length of this Knee pain and function were nail was selected after using a radi- assessed with Hospital for Special opaque ruler, or by measuring the Surgery (HSS) knee scores.15 Patients contralateral femur in case of severe were assigned one of the standard comminution; the selected width was clinical categories: excellent (90-100 1 mm less than the largest reamer points), good (80-89 points), fair (70- diameter. Distal locking was done 79 points), poor (<70 points). Plain with the insertion handle jig, and films of the involved femur and ipsi- proximal locking was performed with lateral hip and knee were obtained. the freehand technique. Radiographic union was defined as The rehabilitation protocol was presence of a bridging callus across 3 identical for each patient. Figure 2. Fifty-five-year-old man with cortices on anteroposterior and lateral distal shaft femur fracture caused by a gunshot. Anteroposterior (A) and plain films. Clinical union was diag- RESULTS lateral (B) plain films obtained 18 nosed when there was no pain with Thirty-one patients (25 men, 6 months after retrograde intramedul- ambulation or single leg stance.9,14 women) with 35 femur fractures were lary nailing show fracture union. 326 The American Journal of Orthopedics® R. Reina et al Mean knee range of motion (ROM) pudendal nerve palsy, and need for a metallurgy, malunion, nonunion, and was 126° (range, 85°-130°). At fol- fracture table. Other limitations are implant failure.2,4 Incidence of knee low-up, 8 (23%) of 35 femur frac- hip stiffness, reduced walking dis- pain after retrograde IMN for femoral tures showed loss of knee ROM; of tance, Trendelenburg gait, weak hip shaft fractures has varied from 0% to these, 5 had lost more than 10° of abductors, difficult entry point, and 60%.3-5,7-9,14,21 In a comparative study ROM, and the remaining patients had hip or thigh pain.1,3,6,10,14 of retrograde versus antegrade nail- less than 10° of limitation.
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