Strength of Fixation Constructs for Basilar Osteotomies of the First Metatarsal

Foot & Ankle ◽  
1992 ◽  
Vol 13 (9) ◽  
pp. 509-514 ◽  
Author(s):  
George J. Lian ◽  
Keith Markolf ◽  
Andrea Cracchiolo
Keyword(s):  
Bending Strength ◽  
Bending Moment ◽  
Metatarsal Head ◽  
Fixation Strength ◽  
Osteotomy Site ◽  
Test Machine ◽  
First Metatarsal ◽  
Single Screw ◽  
Fresh Frozen ◽  
K Wires

Twenty-four pairs of fresh-frozen human feet had a proximal osteotomy of the first metatarsal that was fixed using either screws, staples, or K wires. Each metatarsal was excised and the specimen was loaded to failure in a cantilever beam configuration by applying a superiorly directed force to the metatarsal head using an MTS ser-vohydraulic test machine. Specimens with a crescentic osteotomy that were fixed using a single screw demonstrated higher mean failure moments than pairs that were fixed with four staples or two K wires; staples were the weakest construct. All specimens fixed with staples failed by bending of the staples without bony fracture; all K wire constructs but one failed by wire bending. Chevron and crescentic osteotomies fixed with a single screw demonstrated equal bending strengths; the bending strength of an oblique osteotomy fixed with two screws was 82% greater than for a crescentic osteotomy fixed with a single screw. Basilar osteotomies of the first metatarsal are useful in correcting metatarsus primus varus often associated with hallux valgus pathology. Fixation strength is an important consideration since weightbearing forces on the head of the first metatarsal acting at a distance from the osteotomy site subject the construct to a dorsiflexion bending moment, as simulated in our tests. Our results show that screw fixation is the strongest method for stabilizing a basilar osteotomy. Based upon the relatively low bending strengths of the staple and K wire constructs, we would not recommend these forms of fixation. If, for some reason, these are the only methods of fixation available, then use of a short leg cast and limited weightbearing for several weeks postoperatively should be considered.

Great Toe Metatarsophalangeal Joint Arthrodesis: A User-Friendly Technique

Foot & Ankle ◽  
1992 ◽  
Vol 13 (7) ◽  
pp. 367-377 ◽  
Author(s):  
Ronald W. Smith ◽  
Terry L. Joanis ◽  
Phyllis D. Maxwell
Keyword(s):  
Hallux Valgus ◽  
Metatarsophalangeal Joint ◽  
Metatarsal Head ◽  
Hallux Rigidus ◽  
First Metatarsal ◽  
Pin Fixation ◽  
Patient Responses ◽  
K Wires ◽  
User Friendly

Thirty-four feet (23 patients) were treated with a metatarsophalangeal (MP) joint fusion of the hallux using five threaded 0.062-in K wires for fixation. Operations were done for the following diagnoses: rheumatoid arthritis (26 procedures), hallux rigidus (1), salvage of previous bunionectomies (3), hallux valgus with absent toe, bilateral fusion (2), severe hallux valgus with chronic MP joint synovitis (1), and congenital hallux varus (1). The ages ranged from 17 to 73 years, with an average of 55 years. Follow-up was available on 31 of the fusions by questionnaire and telephone contact, with an average follow-up of 24 months and a minimum of 1 year. The successful arthrodesis rate was 97%. In 9% of the procedures (three cases), the patients were dissatisfied: This was due to pain under the first metatarsal head in two cases and to impingement between the first and second toes in a third case. In 91% of the fusions (29 of 32 patient responses), the patients stated that they would have the surgery if they had to choose again. Patients indicated “complete satisfaction” in 15 fusions and “satisfaction with reservations” in 14. Patients felt that their ability to wear desired shoes was improved in 48% of the procedures, was unchanged by the fusions in 26%, and was worse than before the operation in 26%. Based on this study and review of the literature, a recommendation is made for fusing the rheumatoid hallux with 25° to 30° of valgus and 10° of extension. In general, selection of toe position for fusion is based on reducing stress on the hallux interphalangeal joint and accommodating the position of the second toe. The multiple pin fixation technique gives a high incidence of fusion, it is easy to perform, and it is adaptable to the varying requirements for toe position.

scholarly journals Accessibility of the Metatarsal Head Comparing Distraction and Plantarflexion in a 2-Portal Technique for First Metatarsophalangeal (MTP 1) Joint Arthroscopy

2020 ◽  
Vol 5 (4) ◽  
pp. 2473011420S0049
Author(s):  
Madeleine Willegger ◽  
Katharina Czerny ◽  
Lena Hirtler
Keyword(s):  
Osteochondral Lesion ◽  
Metatarsal Head ◽  
Osteochondral Lesions ◽  
Surgical Equipment ◽  
First Metatarsal ◽  
Non Invasive ◽  
Fresh Frozen ◽  
The Mean ◽  
Portal Technique ◽  
Accessible Area

Category: Arthroscopy; Midfoot/Forefoot Introduction/Purpose: Arthroscopic treatment of osteochondral lesion of the first metatarsophalangeal (MTP1) joint is an established procedure. Non-invasive distraction is most commonly applied when a dorsal 2-portal technique is used. Alternatively, plantarflexion can be utilized. In order to compare the arthroscopic reachability of the first metatarsal head, a laboratory study in anatomical specimens was performed. Methods: Twenty matched pairs (n=40) of fresh-frozen lower leg specimens were obtained and randomly assigned into two groups, a distraction (DIS) and a plantarflexion (PF) group, respectively. A standard 2-portal approach (dorsolateral and dorsomedial portals) with a 1.9mm 30° scope was used. The arthroscopic accessibility of the first metatarsal head was evaluated using chondral picks. Markings at the metatarsal heads were made intraoperatively and measured after exarticulation. Results: In the DIS group the mean accessible area was 58.03%, while the accessible area in the PF group was 55.93%. Though there is a small difference between the two groups, this difference was not statistically significant (p=0.51). Range of motion of the MTP 1 joint did not affect reachability. In one specimen (2.5%) the dorsomedial hallucal nerve was injured during arthroscopy. Conclusion: Access to the MTP1-joint for the treatment of osteochondral lesions is similar using distraction or plantarflexion during arthroscopy. The plantarflexion technique has the advantage of less surgical equipment needed. The dorsomedial hallucal nerve is at danger at the medial portal.

Distal Soft Tissue Release Using Direct and Indirect Approaches: An Anatomic Study

1996 ◽  
Vol 17 (8) ◽  
pp. 458-463 ◽  
Author(s):  
Ian Lin ◽  
Susan K. Bonar ◽  
Robert B. Anderson ◽  
W. Hodges Davis
Keyword(s):  
Soft Tissue ◽  
Hallux Valgus ◽  
Metatarsal Head ◽  
Soft Tissue Release ◽  
Surgical Approaches ◽  
Suspensory Ligament ◽  
First Metatarsal ◽  
Medial Eminence ◽  
Fresh Frozen ◽  
Adductor Hallucis

Two surgical approaches for distal soft tissue release in the correction of hallux valgus, one using a dorsal first web space incision and the other a longitudinal medial capsulotomy incision (used also for medial eminence resection), were studied to compare and delineate the structures actually incised. Anatomic dissections were performed on six fresh-frozen amputation specimens using each of the approaches. The adequacy of release of the adductor hallucis, transverse and oblique heads, first metatarsophalangeal lateral capsule, and suspensory ligament was reviewed. Any inadvertent damage to the first metatarsal head cartilage, second metatarsophalangeal capsule, and lateral head of the flexor hallucis brevis tendon was also noted. Distal soft tissue release is thought to be an important part of hallux valgus surgery. Based on our anatomic dissections, the actual extent of the release may be inconsistent and unpredictable, and may have implications for the predictability of results after hallux valgus surgery.

Comparison of Stability of Proximal Crescentic Metatarsal Osteotomy and Proximal Horizontal “V” Osteotomy

1994 ◽  
Vol 15 (5) ◽  
pp. 263-270 ◽  
Author(s):  
Leland C. McCluskey ◽  
Jeffrey E. Johnson ◽  
George T. Wynarsky ◽  
Gerald F. Harris
Keyword(s):  
Metatarsal Head ◽  
Metatarsal Osteotomy ◽  
Plantar Surface ◽  
Cortical Screw ◽  
Fixation Techniques ◽  
Fresh Frozen ◽  
Rapid Healing ◽  
K Wires ◽  
The Stability ◽  
Screw Group

Proximal metatarsal osteotomies are often performed in patients with hallux valgus and significant metatarsus primus varus. The crescentic osteotomy is popular; however, some authors have reported malunion of the metatarsal shaft caused by dorsal angulation of the osteotomy in a significant number of cases. Recently, proximal transverse “V” osteotomies have been reported to have good results, with rapid healing and no dorsal malunions. We compared the stability of a transverse, proximal “V” osteotomy, using two 0.062-inch K-wires or a 3.5-mm cortical screw for fixation, with that of the proximal crescentic osteotomy, using a 3.5-mm cortical screw fixation. The three osteotomy/fixation techniques were performed on 30 fresh-frozen cadaver feet. The specimens were loaded to failure at the fixation site by applying a load through the plantar surface of the first metatarsal head. Force versus displacement curves were obtained to calculate the failure load and stiffness. Statistical differences among the three groups were determined by the nonparametric Mann-Whitney U-test and the standard t-test. The “V” osteotomy/screw group was more stable than either the “V” osteotomy/pin group or the crescentic osteotomy/screw group. Differences in failure strength between the “V”/screw group and the other two groups were significant at the P < .01 level and the differences in stiffness were significant at the P = .05 level. No statistical differences were found between the “V”/pins and the crescentic/screw groups.

Biomechanical Comparison of a Novel Method of Tricortical Kirschner Wire Fixation of Distal Chevron Osteotomies of the First Metatarsal Versus Traditional Kirschner Wire and Versus Screw Fixation

2020 ◽  
pp. 193864002096533
Author(s):  
Jie Chen ◽  
Natalie R. Black ◽  
Randall Morris ◽  
Vinod K. Panchbhavi
Keyword(s):  
Screw Fixation ◽  
Kirschner Wire ◽  
Matched Pair ◽  
Stiffness Ratio ◽  
First Metatarsal ◽  
Single Screw ◽  
Chevron Osteotomy ◽  
Wire Fixation ◽  
Load To Failure ◽  
K Wires

Introduction: Traditional Kirschner wire (K-wire) stabilization of first metatarsal distal chevron osteotomy involves 1 cortex of fixation; however, unicortical fixation is associated with a high complication rate, including pin migration. A method of K-wire fixation utilizing 3 cortices may be biomechanically superior and potentially equivalent to single-screw fixation. Methods: Cadaveric specimens fixed with tricortical K-wires were tested in both the physiologic and cantilever conditions against specimens fixed with unicortical K-wires (N = 8) and single screws (N = 9) utilizing matched-pair comparison groups. Differences in physiologic and cantilever fixed/intact stiffness ratio and cantilever failure load were determined. Results: The tricortical fixation specimens had a significantly higher stiffness ratio in cantilever loading than the unicortical fixation specimens (60.50% tricortical, 34.17% unicortical, P = .02) but not in physiologic load (15.34% tricortical, 25.75% unicortical, P = .23). In cantilever failure loading, the tricortical fixation specimens had a significantly higher load to failure than the unicortical fixation specimens (132.81 N tricortical, 58.58 N unicortical, P < .01). Stiffness ratio under physiologic load, cantilever load, and ultimate load to failure were not significantly different between tricortical K-wire and screw-fixation groups. Conclusion: Tricortical K-wire fixation for distal chevron osteotomies is biomechanically superior to traditional unicortical K-wire fixation, and equivalent to single-screw fixation. Levels of Evidence: Level V: Cadaver study

The Hallux Metatarsophalangeal Capsule: An Anatomic Study With Respect to Percutaneous Hallux Valgus Correction

2021 ◽  
pp. 107110072110272
Author(s):  
Kenneth M. Chin ◽  
Nicholas S. Richardson ◽  
John T. Campbell ◽  
Clifford L. Jeng ◽  
Matthew W. Christian ◽  
...  
Keyword(s):  
Minimally Invasive ◽  
Hallux Valgus ◽  
Metatarsal Head ◽  
Cadaveric Study ◽  
Anatomic Study ◽  
Orthopedic Surgeons ◽  
Popular Knowledge ◽  
Fresh Frozen ◽  
The Mean ◽  
Anatomic Relationship

Background: Minimally invasive surgery for the treatment of hallux valgus deformities has become increasingly popular. Knowledge of the location of the hallux metatarsophalangeal (MTP) proximal capsular origin on the metatarsal neck is essential for surgeons in planning and executing extracapsular corrective osteotomies. A cadaveric study was undertaken to further study this anatomic relationship. Methods: Ten nonpaired fresh-frozen frozen cadaveric specimens were used for this study. Careful dissection was performed, and the capsular origin of the hallux MTP joint was measured from the central portion of the metatarsal head in the medial, lateral, dorsal, plantarmedial, and plantarlateral dimensions. Results: The ten specimens had a mean age of 77 years, with 5 female and 5 male. The mean distances from the central hallux metatarsal head to the MTP capsular origin were 15.2 mm dorsally, 8.4 mm medially, 9.6 mm laterally, 19.3 mm plantarmedially, and 21.0 mm plantarlaterally. Conclusion: The MTP capsular origin at the hallux metatarsal varies at different anatomic positions. Knowledge of this capsular anatomy is critical for orthopedic surgeons when planning and performing minimally invasive distal metatarsal osteotomies for the correction of hallux valgus. Type of Study: Cadaveric Study.

Radiographic Measurements of the Affected and Unaffected Feet in Patients with Unilateral Hallux Limitus

2016 ◽  
Vol 106 (3) ◽  
pp. 172-181
Author(s):  
Andrew F. Knox ◽  
Alan R. Bryant
Keyword(s):  
Metatarsal Head ◽  
Radiographic Evaluation ◽  
Head Shape ◽  
Intrinsic Factors ◽  
Hallux Limitus ◽  
First Metatarsal ◽  
Radiographic Measurements ◽  
Angle Data ◽  
Significant Difference ◽  
First Ray

Background: Controversy exists regarding the structural and functional causes of hallux limitus, including metatarsus primus elevatus, a long first metatarsal, first-ray hypermobility, the shape of the first metatarsal head, and the presence of hallux interphalangeus. Some articles have reported on the radiographic evaluation of these measurements in feet affected by hallux limitus, but no study has directly compared the affected and unaffected feet in patients with unilateral hallux limitus. This case-control pilot study aimed to establish whether any such differences exist. Methods: Dorsoplantar and lateral weightbearing radiographs of both feet in 30 patients with unilateral hallux limitus were assessed for grade of disease, lateral intermetatarsal angle, metatarsal protrusion distance, plantar gapping at the first metatarsocuneiform joint, metatarsal head shape, and hallux abductus interphalangeus angle. Data analysis was performed using a statistical software program. Results: Mean radiographic measurements for affected and unaffected feet demonstrated that metatarsus primus elevatus, a short first metatarsal, first-ray hypermobility, a flat metatarsal head shape, and hallux interphalangeus were prevalent in both feet. There was no statistically significant difference between feet for any of the radiographic parameters measured (Mann-Whitney U tests, independent-samples t tests, and Pearson χ2 tests: P &gt; .05). Conclusions: No significant differences exist in the presence of the structural risk factors examined between affected and unaffected feet in patients with unilateral hallux limitus. The influence of other intrinsic factors, including footedness and family history, should be investigated further.

scholarly journals Effect of Slam Force Duration on the Vibratory Response of a Lightweight High-Speed Wave-Piercing Catamaran

2015 ◽  
Vol 59 (02) ◽  
pp. 69-84
Author(s):  
Jason John McVicar ◽  
Jason Lavroff ◽  
Michael Richard Davis ◽  
Giles Thomas
Keyword(s):  
High Speed ◽  
Bending Strength ◽  
Experimental Studies ◽  
Bending Moment ◽  
Higher Order ◽  
Acute Angle ◽  
Beam Model ◽  
Higher Order Modes ◽  
Hull Structure ◽  
Vertical Bending Moment

When the surface of a ship meets the water surface at an acute angle with a high relative velocity, significant short-duration forces can act on the hull plating. Such an event is referred to as a slam. Slam loads imparted on ships are generally considered to be of an impulsive nature. As such, slam loads induce vibration in the global hull structure that has implications for both hull girder bending strength and fatigue life of a vessel. A modal method is often used for structural analysis whereby higher order modes are neglected to reduce computational effort. The effect of the slam load temporal distribution on the whipping response and vertical bending moment are investigated here by using a continuous beam model with application to a 112 m INCAT wave-piercing catamaran and correlation to full-scale and model-scale experimental data. Experimental studies have indicated that the vertical bending moment is dominated by the fundamental longitudinal bending mode of the structure. However, it is shown here that although the fundamental mode is dominant in the global structural response, the higher order modes play a significant role in the early stages of the response and may not be readily identifiable if measurements are not taken sufficiently close to the slam location. A relationship between the slam duration and the relative modal response magnitudes is found, which is useful in determining the appropriate truncation of a modal solution.

Plantar Pressure and Load in Cadaver Feet After a Weil or Chevron Osteotomy

2005 ◽  
Vol 26 (2) ◽  
pp. 158-165 ◽  
Author(s):  
John Snyder ◽  
John Owen ◽  
Jennifer Wayne ◽  
Robert Adelaar
Keyword(s):  
Contact Area ◽  
Plantar Pressure ◽  
Metatarsal Osteotomy ◽  
Plantar Surface ◽  
First Metatarsal ◽  
The Third ◽  
Load Transmission ◽  
Chevron Osteotomy ◽  
First Ray ◽  
Fresh Frozen

Background: Since metatarsal osteotomy was first used to treat metatarsalgia in the early twentieth century, many techniques have been described to accomplish the basic aim of reduction of load transmission through the operated metatarsal and reduction of localized high pressure on the plantar surface of the metatarsal. Our study examined two popular distal metatarsal neck osteotomies used for the relief of central metatarsalgia and the biomechanical changes that result from their use in a cadaver forefoot model. Methods: After applying 445N (100 lbs) of axially directed force, we measured plantar pressure using the TekScan HR Mat™ (TekScan, Inc., South Boston, MA) in twelve paired, thawed, fresh-frozen intact cadaver legs, then after either a Weil or chevron osteotomy of the second metatarsal and finally after the addition of the same osteotomy of the third metatarsal. Results: Load in the forefoot was not significantly affected by the Weil osteotomy. A significant increase in load was produced in the first metatarsal region, and significant decreases in load were produced beneath the operated metatarsal heads after the chevron osteotomy. Average pressure in the contact area of the forefoot showed similar trends; however, load and pressure changes occurred independently, owing to the changes in contact area produced by the osteotomies. No significant changes were observed in the nonoperated metatarsal regions. Conclusions: In this model, the chevron osteotomy more effectively reduced load and plantar pressure in the operated metatarsal regions; however, increases in load and pressure were observed in the first metatarsal region. The increase in pressure without a change in load in region 3 (third metatarsal) after a Weil osteotomy of the third metatarsal was attributed to the creation of a plantar prominence. This study did not show a reduction in load transmission as a result of the Weil osteotomy, which contradicts the proposed mechanism of clinical benefit. An intact first ray likely prevents transfer of load or pressure to adjacent lesser metatarsals with chevron osteotomy.

Sign in / Sign up

Export Citation Format

Share Document