Semiextended intramedullary nailing of the tibia using a suprapatellar approach: radiographic results and clinical outcomes at a minimum of 12 months follow-up.

OBJECTIVE: To evaluate the clinical and radiographic results associated with the use of a percutaneous suprapatellar (SP) portal and accompanying instrumentation for tibial intramedullary nail (IMN) insertion using a semiextended approach.
DESIGN: Prospective, nonrandomized, nonconsecutive study.
SETTING: Level 1 trauma center. PATIENTS AND METHODS: From June 2007 to January 2011, 56 fractures (55 patients) underwent intramedullary nailing of a tibia fracture with a semiextended approach through a SP portal. Radiographic and clinical follow-up examinations were performed at a minimum of 1 year after the index procedure. Measurements included bone healing, tibial alignment, knee range of motion, pain drawings, pain scoring (visual analogue scale), functional outcome (Lysholm and SF-36 scoring), evaluation of prenail and postnail insertion arthroscopic images of the patella-femoral (PF) joint (subgroup of study patients), and 1-year follow-up magnetic resonance imaging (MRI) scans (STIR and T2 gradient echo) of the knee to evaluate the PF joint cartilage. MRI scans were reviewed by an independent bone radiologist, whereas arthroscopic images were evaluated by an independent sports medicine fellowship-trained orthopaedic surgeon.
RESULTS: Thirty-six patients (37 fractures) were available for follow-up at a minimum of 1 year (range: 12-49 months) after the index procedure. All but 2 fractures healed after the index procedure (94.6%). There was 1 radiographic malunion (2.7%). The mean Lysholm knee score was 82.14. Mean SF-36 physical and mental scores were 40.8 and 46.0, respectively. Mean arc of knee motion was 124.4 degrees for the affected extremity compared with 127.2 degrees for the contralateral knee. One patient (2.7%) complained of mild pain at the scar, but no patient complained of anterior knee pain either at the PF joint or at the anterior proximal tibia. In 13 of 15 patients undergoing an arthroscopic assessment of the PF joint, prenail and postnail insertion, no cartilage changes, or pressure points were seen either at the patella or at the trochlea groove. Two patients had grade II chondromalacia of the trochlea immediately after the procedure, but these did not correspond with either MRI scans or clinical findings at 1 year. When the remainder of the 1-year MRI scans were reviewed, 1 knee (2.7%) in a patient that did not have an arthroscopic examination was found to have grade II chondromalacia in the PF joint, but this did not correlate with the clinical examination, which was normal.
CONCLUSIONS: This is the first paper to critically document clinical and radiographic results using the percutaneous SP portal with the semiextended approach for IMN of the tibia. Our 1 year results indicate that the procedure resulted in excellent tibial alignment, union, and knee range of motion, with rare sequelae in the PF joint based on immediate arthroscopy and 1-year MRI scans and clinical examinations. Even more interesting was the absence of anterior tibial pain often found when a tibial nail is inserted in a standard fashion.