Percutaneous Compression Plate Group Research Articles

Comparison of percutaneous compression plate to parallel screws in the treatment of nondisplaced femoral neck fractures in elderly patients: a prospective, randomized study.

The optimal internal fixation for non-displaced femoral neck fractures remains controversial. This study aimed to compare the clinical results of the percutaneous compression plate (PCCP) with parallel screws (PS) in treating femoral neck fractures in elderly patients. A total of 218 patients who underwent internal fixation were randomized to receive either a percutaneous compression plate (PCCP group) or parallel screws (PS group) using a computerized random sequence generator which was used to assign the order of randomization. Patients were assessed by the operating time, intraoperative blood loss, hemoglobin level drop, postoperative hospital stay, the time to full weight-bearing, reduction quality, fracture healing time, Harris hip score, and postoperative complications. There was no significant difference between PCCP and PS groups regarding operative time, intraoperative blood loss, hemoglobin level drop, postoperative hospital stays, reduction quality, and Harris hip score (p > 0.05). The time to full weight-bearing and the fracture healing time in the PCCP group were shorter than those in the PS group (p < 0.05). The overall complication rates were slightly lower in the PCCP compared to the PS patients, but there was no significant difference (p > 0.05). However, the implant failure rate was significantly higher in the PS group compared to the PCCP group (p < 0.05). The present study suggests that the PCCP is superior to the parallel screws fixation in the treatment of non-displaced elderly femoral neck fractures in terms of earlier full weight-bearing, shorter fracture healing time, and lower implant failure rate. Therefore, it may be a better therapeutic strategy for non-displaced femoral neck fractures in elderly patients.

Comparison of curative effect between percutaneous compression plate and cannulated compression screw in the treatment of displaced femoral neck fractures in young and middle-aged patients

To compare the efficacy of percutaneous compression plate and cannulated compression screw in the treatment of displaced femoral neck fractures in young and middle-aged patients. From January 2015 to July 2020, 68 young and middle-aged patients with displaced femoral neck fracture were retrospectively analyzed. Among them, 31 cases were fixed by percutaneous compression plate (PCCP), and 37 cases were fixed by cannulated compression screw (CCS). General data such as gender, age, cause of injury, comorbidities, fracture classification and cause of injury of two groups were collected. The operation time, intraoperative blood loss, hospital stay, full weight bearing time, fracture healing time, visual analogue scale(VAS), Harris hip score and complications were compared between two groups. Patients in both groups were followed up for more than 2 years. There were no significant differences in operation time, intraoperative blood loss, fracture reduction quality, hospital stay and VAS between two groups. The fracture healing time in PCCP group was significantly shorter than that in CCS group (t=-4.404, P=0.000). The complete weight bearing time of PCCP group was significantly shorter than that of CCS group (t=-9.011, P=0.000). Harris score of hip joint in PCCP group was better than that in CCS group 2 years after operation (P=0.002). Complications occurred in 3 cases (9.68%) in PCCP group, while 11 cases (29.72%) in CCS group, with a statistically significant difference (P=0.042). Both PCCP and CCS can be used for the treatment of displaced femoral neck fractures in young and middle-aged people. Compared with CCS, PCCP fixation can achieve shorter fracture healing time and create conditions for early full weight bearing. PCCP results in higher hip score and lower complications.

Comparison of Curative Effect between PFNA and PCCP in the Treatment of Femoral Intertrochanteric Fractures.

Objective To compare and analyze the clinical efficacy of proximal femoral nail anti-rotation (PFNA) and percutaneous compression plate (PCCP) for minimally invasive treatment of femoral intertrochanteric fractures. Methods A retrospective analysis of 98 patients with femoral intertrochanteric fractures admitted to our hospital from January 2019 to December 2020 was used as the research object, and they were divided into PFNA group and PCCP group according to different treatment methods, with 51 cases and 47 cases. The intraoperative and postoperative indicators were compared between the two groups of patients. Results There was no significant difference in the operative time, postoperative fracture healing time, and Harris score of hip joint function between the two groups (t = −1.43, 1.86, 1.63; P > 0.05). Compared with the PFNA group, the intraoperative blood loss and postoperative drainage volume in the PCCP group were lower than those in the PFNA group (t = 11.38, 9.66; P < 0.05). Compared with the PFNA group, the time of weight-bearing in the PCCP group was longer than that in the PFNA group (t = −2.23, P < 0.05). The total incidence of postoperative complications was 7.84% in the PFNA group and 10.64% in the PCCP group, and there was no significant difference between the two groups (P > 0.05). Conclusion The PFNA and PCCP are both effective measures for the clinical treatment of intertrochanteric fractures, and internal fixation should be reasonably selected according to the specific conditions of the patients.

Analysis of the Therapeutic Effects of Percutaneous Compression Plate for Femoral Neck Fractures in Young and Middle-Aged Patients: A Retrospective Multicenter and 2-Year Follow-Up Study

Introduction: Traditional internal fixators include hollow compression screw (HCS) and sliding hip screw for femoral neck fractures have a high incidence of complications, and are not conducive to postoperative early rehabilitation and weight-loading of patients. Therefore, femoral neck fractures are referred to as ‘unresolved fractures’. However, single-center results of percutaneous compression plate (PCCP) have showed a significant improvement in efficacy. We retrospectively analyzed the therapeutic effects of PCCP for femoral neck fractures in young and middle-aged patients in a multi-center and &gt;2-year follow-up.&#x0D; Materials and Methods: Between January 2010 and December 2017, 331 patients with femoral neck fractures in young and middle-aged patients fixed with HCS and PCCP in four hospitals were studied retrospectively.&#x0D; Results: There were 182 men and 149 women, with an average age of 47.69 years (age range, 20-65 years). HCS group vs. PCCP group (170 vs. 161). There was no significant difference in the baseline data between the two groups (P&gt;0.05). All patients were followed-up for 24-60 months (mean, 36 months). The operative time and intraoperative bleeding were significantly decreased, whereas the hospital stay significantly longer in HCS group than those in PCCP group (P&lt;0.05). Nonunion in 17 cases and fixation failure in 14 cases in HCS group, whereas 3 and 0 cases, respectively, in PCCP group, showing significant difference (P&lt;0.05). Avascular necrosis (AVN) in 17 cases in HCS group while 15 cases in PCCP group, showing no significant difference (P&gt;0.05). The overall complications in HCS group were greater than that in PCCP group (P&lt;0.05). The Harris hip scores at 6- and 12-month follow-up in group PCCP were significantly improved than those in group HCS (P&lt;0.05), but not significant at 18-, 24- month and last follow-up between the two groups (P&gt;0.05).&#x0D; Conclusion: Our results suggest that PCCP is a stable and reliable internal fixation device with sliding compression effect for femoral neck fractures, which has satisfactory short and mid-term therapeutic effects, but AVN remains unsolved.

Imaging observation of percutaneous compression plate use in promoting femoral neck fracture healing

ObjectiveTo examine the imaging evidence of the use of percutaneous compression plate (PCCP) in promoting femoral neck fracture healing compared with cannulated screws (CS).MethodsThis retrospective study enrolled patients with femoral neck fractures undergoing internal fixation procedures. The patients were divided into a PCCP group and a CS group with imaging as the primary outcome and Harris hip score (HHS) as the secondary outcome.ResultsThis study included 162 patients: 80 in the PCCP group and 82 in the CS group. There were no significant differences between the patients in their preoperative baseline characteristics. Patient follow-up ranged from 24–56 months (mean 30.7 months). Differences in reduction quality, screw slipping, neck shortening and avascular necrosis (AVN) were not significant between the two groups. There were significant differences between the treatment groups in bone absorption, nonunion, healing time, screw withdrawal and fixation failure in favour of the PCCP group. Postoperative HHS at 6 and 12 months were significantly better for the PCCP group than the CS group, but the differences were not significant at 24 months and last follow-up.ConclusionStable internal fixation with dynamic compression was the key to PCCP promoting femoral neck fracture healing.

Effectiveness of percutaneous compression plate fixation for femoral neck fractures

To investigate the effectiveness of percutaneous compression plate (PCCP) fixation for femoral neck fracture. A clinical data of 100 patients with femoral neck fractures who were treated with internal fixation were analyzed retrospectively. The fractures were fixed with the cannulated screws (CS) in 55 patients (CS group) and with the PCCP in 45 patients (PCCP group). There was no significant difference in gender, age, the cause of injury, the fracture type, complications, and disease duration between the two groups ( P>0.05). The quality of fracture reduction, bone resorption, screw slipping, femoral neck shortening, complications (nonunion, failure of fixation, and osteonecrosis of femoral head), and functional recovery of hip (Harris score) were compared between the two groups. All incisions healed by first intention. All patients were followed up 24-56 months, with an average of 30.7 months. The quality of fracture reduction was excellent in 26 cases, good in 18 cases, fair in 9 cases, and poor in 2 cases in CS group and excellent in 21 cases, good in 17 cases, fair in 4 cases, and poor in 3 cases in PCCP group, showing no significant difference between the two groups ( Z=-0.283， P=0.773). The incidence of nonunion in PCCP group was significantly lower than that in CS group ( P=0.046), and the fracture healing time in PCCP group was shorter than that in CS group ( t=2.155, P=0.034). There was no significant difference in the incidences of bone resorption, screw slipping, femoral neck shortening, failure of fixation, and osteonecrosis of femoral head between the two groups ( P>0.05). The overall complication rates were 27.27% (15/55) in CS group and 8.89% (4/45) in PCCP group, showing significant difference ( χ 2=5.435, P=0.020). The Harris score in PCCP group at 6 months after operation was significantly higher than that in CS group ( t=-2.073, P=0.041). However, there was no significant difference in the Harris score at 12, 18, and 24 months after operation between the two groups ( P>0.05). Stable sliding compression of PCCP is benefit for the femoral neck fracture healing, especially shortening union.

Examining implant superiority in the treatment of simple pertrochanteric fractures of the proximal femur in elderly patients.

The aim of this study was to compare the clinical and radiological results of the proximal femoral nail antirotation (PFNA) with those of the dynamic hip screw (DHS) and percutaneous compression plate (PCCP) in the treatment of simple pertrochanteric fractures. A total of 203 patients were included in the study. PFNA fixations were performed in 73 patients (PFNA group), DHS in 68 patients (DHS group), and PCCP in 62 patients (PCCP group). The main outcome measurements were perioperative properties, the Harris hip score, changes in the neck-shaft angle, and loss of the abductor muscle strength. Data were compared between the groups. The mean estimated total blood loss and the number of patients receiving the blood transfusion rate in the PFNA group were statistically significantly lower. The mean operation and fluoroscopy times in the PCCP group were statistically significantly higher. The mean loss of the abductor muscle strength and changes in the neck-shaft angle in the PFNA group were statistically significantly higher. The mean Harris hip scores were similar. Our findings demonstrated that although PFNA was superior with regard to the perioperative data, DHS and PCCP were superior in maintaining the reduction and the abductor muscle strenght. All three implants were similar and had satisfactory functional outcomes.

Comparison of fixations with dynamic hip screw, percutaneous compression plate and proximal femoral nail anti-rotation for intertrochanteric femoral fractures with paries medialis defect

Objective To compare the effects of fixations with dynamic hip screw (DHS), percutaneous compression plate (PCCP) and proximal femoral nail anti-rotation (PFNA) for treatment of intertrochanteric femoral fractures with paries medialis defect. Methods We reviewed the 82 patients with femoral intertrochanteric fracture and paries medialis defect who had been treated at our department from January 2011 to July 2016. They were 42 men and 40 women, aged from 27 to 91 years (average, 73.0 years). According to the AO classification, 72 cases belonged to type 31-A2.2, 10 to type 31-A2.3. Of them, 9 cases were treated with DHS, 17 cases with PCCP and 56 cases with PFNA-Ⅱ. The 3 groups were compared in terms of intraoperative blood loss, blood infusion, fluid infusion, operation duration, time for fracture union, postoperative complications and Functional Recovery Score (FRS) of the hip 12 months after operation. Results The fluid infusion [1,100 (850, 1,100) mL] and intraoperative blood loss [60 (5, 100) mL] in the PCCP group were significantly less than in the PFNA group [1,100 (1,000, 1,700) mL and 150 (50, 300) mL] and the operation duration (91.4±29.2 min) in the former was significantly shorter than in the latter [121 (85, 185) min] (P 0.05). Of the patients, 57 (8 DHS, 12 PCCP and 37 PFNA ones) were followed up for an average of 47 months (from 15 to 85 months). There were no statistically significant differences between the 3 groups in time for fracture union, complications, or average FRS score of the hip 12 months after operation (P>0.05). Conclusions For unstable intertrochanteric fractures with paries medialis defect, it is not clear that intramedullary nails are superior to extramedullary fixation. Intramedullary nails like PFNA may be suggested for patients with better preoperative conditions while extramedullary fixation like PCCP suggested for those with poor general conditions. Key words: Hip fractures; Fracture fixation, internal; Bone plates; Bone nails

Comparison of percutaneous compression plate and cannulated compression screw in treatment of undisplaced femoral neck fracture in the elderly

Objective To compare the efficacy between percutaneous compression plate (PCCP) and cannulated compression screw for undisplaced femoral neck fracture among the elderly. Methods A retrospective case-control study was made on 46 elderly patients with undisplaced femoral neck fracture between August 2011 and September 2015. There were 14 males and 32 females, with the age of(76.9±12.1) years (range, 60-85 years). The fracture types included GardenⅠ in 12 patients and GardenⅡ in 34. These patients were divided into PCCP group (PCCP for undisplaced femoral neck fracture in 23 patients) and cannulated screw group (three cannulated compression screws for undisplaced femoral neck fracture in 23 patients), according to different surgical fixations. The following data were compared between two groups, namely, operation time, intraoperative blood loss, postoperative hemoglobin decline, postoperative length of hospital stay, postoperative partial time of weight-bearing and full weight-bearing, fracture healing time, Harris hip score (HHS) as well as postoperative complications. Results All 46 patients were followed up, with follow-up duration for (34.6±15.3)months (range, 12-60 months) in PCCP group and for (32.9±17.3) months (range, 12-60 months) in cannulated screw group (P>0.05). There were no statistically significant difference between two groups in terms of operation time, intraoperative blood loss, postoperative hemoglobin decline, postoperative length of hospital stay, fracture healing time, and postoperative full weight-bearing time (P>0.05). The partial weight-bearing time of patients in PCCP group was earlier than that in cannulated screw group (P 0.05). There was no statistically significant difference in the incidence of postoperative complications between PCCP group (9%) and the cannulated screw group (13%) (P>0.05). Conclusions Usage of PCCP or cannulated compression screw can obtain satisfactory clinical results for the undisplaced femoral neck fracture among the elderly. But PCCP has the advantages of earlier partial weight-bearing time and faster recovery. Key words: Femoral neck fractures; Fracture fixation, internal; Bone plates

Minimally invasive percutaneous compression plating versus dynamic hip screw for intertrochanteric fractures: a randomized control trial

ObjectiveIntertrochanteric femur fracture is a common injury in elderly patients. The dynamic hip screw (DHS) has served as the standard choice for fixation; however it has several drawbacks. Studies of the percutaneous compression plate (PCCP) are still inconclusive in regards to its efficacy and safety. By comparing the two methods, we assessed their clinical therapeutic outcome. MethodsA total of 121 elderly patients with intertrochanteric femur fractures (type AO/OTA 31.A1-A2, Evans type 1) were divided randomly into two groups undergoing either a minimally invasive PCCP procedure or a conventional DHS fixation. ResultsThe mean operation duration was significantly shorter in the PCCP group (55.2min versus 88.5min, P<0.01). The blood loss was 156.5ml±18.3ml in the PCCP group and 513.2ml±66.2ml in the DHS group (P<0.01). Among the patients treated with PCCP, 3.1% needed blood transfusions, compared with 44.6% of those that had DHS surgery (P<0.01). The PCCP group displayed less postoperative complications (P<0.05). The mean American Society of Anesthesiologists score and Harris hip score in the PCCP group were better than those in the DHS group. There were no significant differences in the mean hospital stay, mortality rates, or fracture healing. ConclusionDue to several advantages, PCCP has the potential to become the ideal choice for treating intertrochanteric fractures (type AO/OTA 31.A1-A2, Evans type 1), particularly in the elderly.

Percutaneous compression plate versus proximal femoral nail anti-rotation in treating elderly patients with intertrochanteric fractures: a prospective randomized study

BackgroundThe treatment and management of hip fracture poses a great challenge for clinicians in osteology and surgery. The aim of this study is to compare the clinical effectiveness of the percutaneous compression plate (PCCP) versus proximal femoral nail anti-rotation (PFNA) in the treatment of intertrochanteric fractures in elderly patients. MethodsA prospective randomized study was carried out from January 2008 to October 2011 involving 90 elderly patients with intertrochanteric fractures (90 hips) who underwent minimally invasive surgery using the PCCP or PFNA. Evaluation variables, including operation time, intra- and perioperative blood loss, duration of hospital stay, incidence of postoperative complications, and final clinical outcomes by the end of follow-up, were used to compare the benefits of these two implants. ResultsAmong 90 subjects, 45 received PCCPs and 45 received PFNAs. The baseline characteristics of the two groups were comparable. The median follow-up time was 16.9months (12–24months). In the PCCP group, the mean operative time was 53min (40–75min), and the mean intra- and perioperative blood losses were 100.7ml (60–150ml) and 916ml (433–1339ml), respectively, which were significantly lower than those in the PFNA group. Nevertheless, there was no statistical difference in the incidence of postoperative complications and final clinical outcomes including pain complaints, range of motion of the hip, postoperative hip function at 12months, and the recovery of walking ability to pre-injury status between these two implants. ConclusionsOverall, the PCCP and PFNA appear to have similar clinical effects in treating elderly patients with intertrochanteric fractures, although the PCCP provided shorter operation times and less blood loss than PFNA. Both implants discussed were demonstrated to be ideal for the treatment of femoral intertrochanteric fractures in elderly patients.

A comparative study between gamma nail and percutaneous compression plating for the treatment of intertrochanteric hip fractures.

Nowadays, the literature shows better results in the treatment of intertrochanteric (AO/OTA 31.A1-A2) hip fractures with dynamic hip screw (DHS) compared with gamma nail (GN). Besides, percutaneous compression plate (PCCP) gives results which are better or similar to those obtained with DHS. But only two reports compare the results between PCCP and GN. The aim of this trial is to compare the outcome of treatment of these fractures with either a PCCP or a GN. A retrospective trial with 414 patients over 60years of age treated in our institution for 6years, with a minimum follow-up of 1year, was performed to compare the outcome of a PCCP (240) with a GN (174). The post-operative hospital stay was 2days longer in the GN group compared to the PCCP group (p<0.001). The post-operative haemoglobin serum level was slightly lower in the GN group (relative risk (RR) -0.28, 95% confidence interval (CI): -0.02 to -0.54, p=0.036) and the transfusion requirement was lower in the PCCP group (GN 53.4% vs. PCCP 33.8%, p<0.001). The procedure-related complications rate was higher in the GN group (9.8 vs. 5%, p=0.06). PCCP has lower overall economical cost and blood transfusional requirements for a similar or better outcome in terms of procedure-related complications.

Perioperative Lateral Trochanteric Wall Fractures: Sliding Hip Screw versus Percutaneous Compression Plate for Intertrochanteric Hip Fractures

This study was performed to determine the incidence of perioperative lateral wall fractures with a standard sliding hip screw (SHS) versus a percutaneous compression plate (PCCP) using identical meticulous closed reduction techniques in both groups. Retrospective analysis of a prospective trauma registry. Urban Level I trauma center. Over a 7-year period, 337 patients with intertrochanteric hip fractures were treated with either a SHS or a PCCP at our institution. The PCCP group (Group 1) consisted of 200 patients, of which 141 (71%) had adequate images to be included in the study. The SHS group (Group 2) consisted of 137 patients, of which 100 (73%) had adequate images to be included in the study. Closed reduction and plate application with either a standard sliding hip screw or a percutaneous compression plate for an Orthopaedic Trauma Association 31A1 or 31A2 intertrochanteric hip fracture. : Radiographic evidence of lateral trochanteric wall fracture as measured by intraoperative and perioperative radiographs. There was an overall lateral wall fracture incidence of 20% in the SHS group versus 1.4% in the PCCP group (P < 0.01). For the unstable 31A2 fracture types, there was a lateral wall fracture incidence of 29.8% in the SHS group versus 1.9% in the PCCP group (P < 0.01). Overall, the PCCP group had a significantly decreased incidence of lateral trochanteric wall fracture compared with the SHS group. This difference became greater when just unstable intertrochanteric fractures were analyzed. An anatomic reduction, combined with a device (PCCP) that uses small-diameter defects in the lateral trochanteric wall, essentially eliminates perioperative lateral trochanteric wall fractures.

A prospective, randomised study comparing the percutaneous compression plate and the compression hip screw for the treatment of intertrochanteric fractures of the hip

Limited access surgery is thought to reduce post-operative morbidity and provide faster recovery of function. The percutaneous compression plate (PCCP) is a recently introduced device for the fixation of intertrochanteric fractures with minimal exposure. It has several potential mechanical advantages over the conventional compression hip screw (CHS). Our aim in this prospective, randomised, controlled study was to compare the outcome of patients operated on using these two devices. We randomised 104 patients with intertrochanteric fractures (AO/OTA 31.A1-A2) to surgical treatment with either the PCCP or CHS and followed them for one year postoperatively. The mean operating blood loss was 161.0 ml (8 to 450) in the PCCP group and 374.0 ml (11 to 980) in the CHS group (Student's t-test, p < 0.0001). The pain score and ability to bear weight were significantly better in the PCCP group at six weeks post-operatively. Analysis of the radiographs in a proportion of the patients revealed a reduced amount of medial displacement in the PCCP group (two patients, 4%) compared with the CHS group (10 patients, 18.9%); Fisher's exact test, p < 0.02. The PCCP device was associated with reduced intra-operative blood loss, less postoperative pain and a reduced incidence of collapse of the fracture.

Percutaneous compression plating versus compression hip screw fixation for the treatment of intertrochanteric hip fractures

Percutaneous compression plate (PCCP) devices are used for the fixation of intertrochanteric hip fractures by a minimally invasive technique. One hundred and eight patients who underwent this procedure were retrospectively compared with 155 patients who underwent compression hip screw (CHS) fixation. The general characteristics of the two groups, including age, sex, side of injury and co-morbidities assessed by the ASA score were similar. The operative time was significantly shorter in the PCCP group (67 versus 87 min, p=0.00). Postoperative blood transfusions were not required in 40% of the patients in the PCCP group compared to 24% of the patients in the CHS group (p<0.01). The rate of systemic postoperative complications was lower in the PCCP group (p=0.02) both in univariate and multivariate analyses. A considerable reduction was observed in cardiovascular complications (OR=3.1, p<0.05). Length of hospitalisation, implant failure and mortality rates were not significantly different between the two study groups. We conclude that the PCCP device offers several advantages over CHS device and may improve the current treatment of intertrochanteric hip fractures while maintaining a similar success rate in fracture fixation.

Functional Recovery Following Pertrochanteric Hip Fractures Fixated with the Dynamic Hip Screw vs. the Percutaneous Compression Plate

The Dynamic Hip Screw (DHS) is currently the most frequently used implant for the treatment of pertrochanteric hip fractures. The Percutaneous Compression Plate (PCCP) is a recently developed, alternative device that involves minimal invasive surgery. The objective of the present study was to compare functional recovery following these two surgical procedures. A total of 76 consecutive elderly subjects (mean age and standard deviation, 80.6 ± 5.5) following pertrochanteric hip fracture fixation were evaluated prospectively. Functional recovery was assessed 3 and 12 weeks and 2 years following surgery. Differences between groups 3 weeks postsurgery were found only in pain level during ambulation and in the weight-bearing capability of the operated extremity, which were both in favor of the PCCP. By 3 months, both groups had improved in all measures, but did not reach their preinjury level of independence. However, the PCCP group ambulated with fewer assistive devices and demonstrated better recovery of basic activities of daily living (BADL). While the majority of the subjects from both groups ambulated independently 2 years postsurgery, the PCCP group exhibited less pain during ambulation, was more independent in ADL, and required fewer assistive devices for ambulation. To summarize, the PCCP presents enhanced short- and long-term recovery of functional abilities in comparison to DHS. However, given the limited number of patients, further studies are necessary to substantiate these results.

The Gotfried percutaneous compression plate compared with the conventional classic hip screw for the fixation of intertrochanteric fractures of the hip

We performed a randomised, prospective trial in 111 patients with intertrochanteric fractures of the hip comparing the use of the Gotfried percutaneous compression plate (PCCP) with that of the classic hip screw (CHS). Blood loss and transfusion requirement were less in the PCCP group but the operating time was significantly longer. The complication rate after operation was similar in both groups, and at a minimum follow-up of six months there was no difference in the rates of fracture healing or implant failure. The PCCP gives results which are similar to those obtained with a conventional device. Its suggested advantages seem to be theoretical rather than practical and, being a fixed-angle implant, it is not universally applicable.