The clinical outcome of the reduction of the patellar inferior pole fracture with wire cerclage through a generated bone hole, in combination with patellar concentrator: a retrospective comparative study

Abstract

Objective The patellar inferior pole fracture is typically comminuted. Hence, achieving firm fixation and early activity is highly challenging. In this article, we employed the method of wire cerclage through a generated bone hole to reduce the fracture. Our objective was to compare the clinical efficacy of patellar concentrator alone with a combination of cerclage and patellar concentrator in the treatment of patellar inferior pole fracture. Methods We conducted a retrospective review of patients with patellar inferior pole fractures, who underwent patellar concentrator fixation only (the control group) or cerclage combined with patellar concentrator fixation (the experimental group), performed by a single surgeon, between July 2015 and October 2019. Our analysis included surgical indexes like7 aspects (fracture gap after operation, operation time, intra-operative blood loss, intra-operative number of C-arm fluoroscopies conducted, Insall–Salvati ratio calculated immediately after operation, initial range of motion on the 7th day after operation, and fracture healing time), as well as the Bostman score and complications recorded on 1-, 3-, 6-, and 12-month follow up post operation. Results A total of 94 patients with patellar inferior pole fracture and a minimum 1-year follow up were recruited. Following operation, the control group had 33 (71.74%) patients with a fracture gap of 0–2 mm and 13 (28.26%) patients with a fracture gap greater than 2 mm (P = 0.002). Conversely, the experimental group had 46 (95.83%) patients with a fracture gap of 0–2 mm and 2 (4.17%) patients with a fracture gap greater than 2 mm (P = 0.002). Compared to the control group, the experimental group did not experience enhanced operation time or intra-operative blood loss (P = 0.811, P = 0.823). The Insall–Salvati ratio and initial range of motion in the experimental group were larger than the control group (P = 0.037, P = 0.000). Alternately, the number of intra-operative C-arm fluoroscopies conducted and fracture healing time of the experimental group were considerably less than the control group (P = 0.003, P = 0.000). Moreover, at 1-, 3-, 6-, and 12-month follow ups after operation, the Bostman scores of the experimental group were remarkably higher than the control group (P < 0.05). At 12 months post operation, 23 cases (50%) were classified as excellent, 22 cases (47.83%) were good, and 1 case (2.17%) was poor in the control group (P = 0.005). In the meantime, in the experimental group, 38 cases (79.17%) were deemed as excellent and 10 cases (20.83%) were good (P = 0.005). Lastly, complications were detected in 3 cases (6.52%; 1 case of internal fixation loss, 2 cases of hematoma) within the control group, and in 1 case(2.08%; marginal wound necrosis) within the experimental group. There was no wound infection, implant discomfort, or broken fixation in either group. Conclusion Managing the patellar inferior pole fracture with wire cerclage through a generated bone hole is both simple and effective. Moreover, an additional step of patellar concentrator fixation facilitates early functional exercise, with satisfactory clinical outcome.

Surgical treatment of inferior pole fractures of the patella: a systematic review

“…1A) [6, 9, 18, 23, 27, 30–32] and concentrators ( n = 119, 2 studies; Fig. 1B) [4, 25]. This group excluded devices using plates and screws as a buttress without penetration to the fracture site [5, 15].…”

“…1A ) or concentrators (Fig. 1B) [4, 6, 9, 18, 23, 25, 27, 30–32], and the use of separated vertical wiring (SVW; Fig. 1C ) [5, 7, 10, 20, 33, 38, 42, 43, 45], tension band wiring (TBW; Fig.…”

“…Additional techniques frequently used for augmentation include the use of cerclage wiring ( Fig. 1G) [4, 10, 22, 23, 29, 38, 42, 44] and patellotibial wiring [21, 22, 37, 46]. Combinations of techniques are also employed to treat inferior pole fractures of the patella.…”

Design and Validation of a Smile‐Necklace Plate for Treating Inferior Patellar Pole Avulsion Fractures: A Review and Hypothesis

“…When tightened, it can produce continuous centripetal pressure on the patella to counteract tensile stress, thus repositioning and fixing the fracture and allowing the patient to perform functional knee exercises early after surgery 28 . However, the lower portion of the patellar claw sometimes does not completely encircle the fracture fragment, allowing lateral slippage between fragmented bones 29 . Additionally, the internal fixation failure rate is high, and complications such as decoupling and local augmentation are also possible 30 .…”

“… 28 However, the lower portion of the patellar claw sometimes does not completely encircle the fracture fragment, allowing lateral slippage between fragmented bones. 29 Additionally, the internal fixation failure rate is high, and complications such as decoupling and local augmentation are also possible. 30 Repeated intraoperative flushing with ice and hot water can lead to incisional inflammation and pain, respectively.…”