Partial Patellectomy Research Articles

Incidence, mechanism of injury, and treatment of fractures of the patella in children.

Fractures of the patella in skeletally immature patients are rare. The charts of 185 patients treated for patella fractures at the University of Kentucky Medical Center between 1976 and 1988 were retrospectively reviewed. The 12 patients of these 185 aged 8 to 16 years were included in this study. The incidence was calculated to be 6.5% of all patella fractures. All patients studied were male with an average age of 12.7 years. Sleeve fractures were the most common type of patella fracture observed (five), followed by transverse fractures (four). Ten of the 12 cases required operative management ranging from irrigation and debridement to open reduction and internal fixation. Partial patellectomy was performed when indicated. Indications for operative management in this age group were similar to those for adults. As in adults, the mechanism of injury was predominantly motor vehicle and motorcycle crashes. Laws requiring seatbelt restraints for children should have a positive effect on the incidence of such fractures resulting from dashboard injuries. One mechanism of injury not reported previously was that of a flexed knee striking the gym wall after performing a basketball lay-up because the basket was placed flush with the wall.

Results of treatment of displaced patellar fractures by partial patellectomy.

Results of treatment of displaced patellar fractures by partial patellectomy.

Results of partial patellectomy

We present an assessment of 200 patellar fractures treated mostly (175) by partial patellectomy. In 23 cases in which the quadriceps mechanism was 75% intact (MRC power approximately 4), the fractures were treated conservatively, with an overall acceptable result. The operative series with an average follow-up of 3 years has shown 80.3% excellent to good results. A classification of fractures of the patella, based on the anatomical fracture line and quadriceps functional loss as recorded in 690 case histories, is suggested.

Results of treatment of displaced patellar fractures by partial patellectomy.

The results of partial patellectomy as a treatment for displaced patellar fractures were assessed retrospectively with use of clinical, radiographic, and isokinetic strength-testing criteria. Forty patients who had been followed for an average of 8.4 years were studied. In the extremity that had been operated on, the mean active range of motion was 94 per cent, the circumference of the thigh was 100 per cent, and the strength of the quadriceps was 85 per cent of these measurements in the contralateral extremity. The over-all result was rated as excellent in twenty patients, good in eleven, fair in six, and poor in three. There was a significant statistical correlation between the type of fracture and the outcome. The results of this study indicate that partial patellectomy can be an effective treatment for selected patellar fractures.

Treatment of Patellar Fractures by Partial Patellectomy; A Long Term Follow-up Study

Treatment of Patellar Fractures by Partial Patellectomy; A Long Term Follow-up Study

A Metal-Backed, Rotating-Bearing Patellar Prosthesis to Lower Contact Stress

A congruent-contact, metal-backed, rotating-bearing patellar prosthesis has been used clinically over an 11-year period. The features of this implant include a congruent-contact, rotating bearing attached to a thin metallic anchoring plate fixed to the bone by cruciate fixturing fins. The device was initially used with methylmethacrylate and later used as a cementless, porous-coated, ingrowth fixation implant. The benefits of congruent contact with mobility to adjust its tracking position during flexion and extension help to eliminate axial shear stresses at the bone-prosthesis interface and lower the contact stresses at the bearing-metal interface to improve wear properties. Prostheses were implanted in 515 knees over a period of six months to 11 years. Of these 515 knees, 331 patellar prostheses have been followed for 24 to 132 months (mean, 73 months). Of that group of 331 implants, 141 were cemented and 190 were cementless. Specific complications involving the use of this implant were as follows. One intraoperative vertical midpatellar fracture in a cemented case went on to uneventful healing with an excellent result. Two displaced postoperative transverse midpatellar fractures (0.39%) occurred in two revision total knee arthroplasties that involved major lateral releases. One of those was a cemented revision and required removal of the implant and a partial patellectomy to gain an excellent result. In the other, a noncemented revision, the patient lacks 45 degrees of quadriceps extension and has a poor result following traumatic fracture at three years postsurgery. One patellar dislocation (0.19%) occurred in a 270-pound, osteoarthritic man in whom undersized components were used. No polyethylene wear-through, separation from the metal anchoring plate, or implant breakage was seen in this series. Overall, the performance of this congruent-contact, metal-backed, rotating-bearing patellar prosthesis indicates the prosthesis can provide long-term function and stability with few short-term or long-term complications.

Fractures of the patella treated by operation.

A retrospective analysis of 93 operatively treated fractures of the patella is presented. Tension band fixation was used in 14, circumferential wire in 15 and screw fixation in 19 patients. Partial patellectomy was performed in 35 cases and total patellectomy in 10 cases. The result was considered excellent in 27% of the patients, good in 49%, fair in 16% and poor in 8%. Patients under 30 years of age had better results than the older ones (p less than 0.01). Tension band fixation gave results superior to screw fixation (p less than 0.05) and partial patellectomy superior to total patellectomy (p less than 0.02). The length of the immobilization time in plaster showed no statistical significance. As a result of this investigation tension band fixation and partial patellectomy seem to be the methods of choice in the management of those fractures of the patella which need operative treatment.

Comminuted displaced fractures of the patella

A series of 64 comminuted displaced fractures of the patella is reviewed. Morphologically the fractures can be classified into three groups reflecting the mechanism of injury and the degree of soft tissue damage. All fractures were operated on. Tension band wire was used in 21, partial patellectomy in 33 and total patellectomy in 10 patients. The problem of the management of these fractures is often in making the choice between excision and internal fixation. In this retrospective analysis the results of anterior tension band wire fixation were acceptable even in severe comminuted fractures. Partial excision showed satisfactory results provided that at least three-fifths of the patella could be preserved. Total excision is sometimes clearly unavoidable but should be preceded by sober contemplation whenever considered as the alternative to internal fixation.

Treatment of Patella Fractures

1) The end result of twenty patella fractures which were treated surgically in the past seven years was reviewed.2) Seventeen cases were treated by so called dowble circumferencial wiring method, three were partial patellectomy.3) Dowble circumferencial wiring methoed is characterized by easy reposition and firm fixation.4) The result of partial patellectomy was poor or fair.5) From our results, we suggest almost all cases can be treated by our method, especially fragment fracture of patella is best indication.

Treatment of Patella Fractures

1) The end result of twenty patella fractures which were treated surgically in the past seven years was reviewed.2) Seventeen cases were treated by so called dowble circumferencial wiring method, three were partial patellectomy.3) Dowble circumferencial wiring methoed is characterized by easy reposition and firm fixation.4) The result of partial patellectomy was poor or fair.5) From our results, we suggest almost all cases can be treated by our method, especially fragment fracture of patella is best indication.

Treatment of patellar fractures by partial patellectomy.

Results of treating 238 transverse, longitudinal, and osteochondral fractures of the patella are reviewed. Of these, 89 patients had partial patellectomy and extensor mechanism reconstruction. After an average follow-up of four years, functional results have been excellent; there have been no late patellectomies and traumatic arthritis has not developed. Total patellectomy is recommended only when the entire patella is so severely comminuted that none of it can be used as part of the extensor mechanism of the knee.

The effect of patellectomy on knee function

Thirty-three patients were evaluated after patellectomy for subjective complaints, objective physical findings, quadriceps strength, and knee motion during activities of daily living. Partial and complete patellectomy caused an equal loss of active and passive range of motion. Complete patellectomy resulted in greater ligament instability, quadriceps atrophy, and loss of quadriceps strength compared with partial patellectomy. Complete patellectomy casued a reduction in the degree of stance-phase flexion during level walking and negotiating stairs.

Treatment of Fractures of the Patella by Partial Patellectomy

Treatment of Fractures of the Patella by Partial Patellectomy

Der Knorpelschaden nach Patellafraktur

At least 16 cases of posttraumatic chondromalacia of the patella out of a total of 79 patients operated between 1968 and 1971 were diagnosed on the basis of a questionnaire and follow-up examination. The clinical findings and delineation of this complaint from femoro-patellar osteoarthritis are discussed. The diagnosis was confirmed by arthroscopy in 2 patients. The significance of cartilagenous damage due to direct contusion is pointed out. The mechanisms which result in a degradation of the cartilagenous layer in the weeks following the accident are mentioned. The therapeutic consequences for the treatment of fractures of the patella are as follows: One must aim at exact bony reduction. Macroscopically damaged parts of the cartilage should be removed. Indication to partial patellectomy should be on a broad basis. A long term treatment with salicylic acid or Chloroquin-both of which are said to prevent enzymatic degradation of cartilage-should be considered.